Color development



Patented 29, 1942 I g 1 e I UNITED STATES PATENT OFFICE coma DEVELOPMENTKarl Schinzel, Rochester, N. Y., assignor to Eastman Kodak Company,Rochester, N. Y., a corporation of New Jersey No Drawing. ApplicationJuly 3, 1937, Serial No.

151,811. In Austria July 7, 1936 3 Claims. (Cl. 95-2) This inventionrelates to color photography. the products obtained by linking two orthree and particularly to processes in which insoluble molecules of thelatter with the external amino r non-diffusing coupler or developingcompounds group by means of sebaclnic acid dichloride, cyaare present inthe photographic layers. nuric chloride, triazine tricarboxylicacid-trichio- The processes described herein involve simul- 5 ride.etc., according to the methods for compotaneous production ofcolor-separation images by nents described later, or polyyvalentaminophedirect color development or by reversal, or by nols similarlyprepared from the developer Ediredevelopment of the bleached negativeimage. nol." p-nitrophenols containing an amino group This includes theuse of insoluble or non-diffusor an easily exchangeable halide inorthoor ing compounds in the photographic layers, either meta-position,are especially suited for those condeveloping agents or compounds whichfunction densations with acid chlorides or poly-amines. merely ascouplers, forming a colored image by One must, of course, reduce thenitro-group to coupling with another compound. the amino-group andp-nitro-salicylic acid chloride. Worth mentioning are oo-dibenzhydryll5p-aminophenol obtained by catalytic reduction, p-amlnophenols preparedfrom other cryptophe- Celor develPper5 may be added to the three nols bydiazotization, nitration or nitrosation, emulsiOns Whlch have no effectOn Silver br0mide p am inonaphthol 2 tetramethyldiamino diphen when theyare neutral, but develop each of the ylmethane,benzocarbazol-p-aminophen01, the

A. PRIMARY DEVELOPMENT WITH INSOLUBLE Coma DEVELOPERS threelatenteimages to the proper c0101 Onbath' bis-derivative of o-diphenol,of diaminodinitroing a solution of sodium carbonate or even weakdipheny1hexane and ,octane (diammo groups er alkahes. This is possible on thebasis of my are t t t by dihydroxy groups, nitro groups observation thatthe exposed S11V8I bromide, or reduced, acylated, then introduced intothe that which has been made developable in any positions of thehydroxyl amino groups) of other manner, can be developed by completelyapnaphthol of 1,3 dihydmxy phenamhrene insoluble or at least notnoticeably diifusing color none, or the bis p aminopheno1 of the Germandevelopers. Often coupling takes place also bep t t 488,611.'Paraphenylene diamines with tween added components and developers ofthis one ammo group arylsulfonylated can be composition, but morereadily, of course, between pared to p ammophenols They are dimcultlythese components and a developer in solution. In obtained from highermolecular p diammes by the first case different coupling components anddirect arylsulfonylation, but easily from suitable developers can beadded toeach emulsion, while intermediary products, as t i in the lattercase the components must be selectaminodiphenyl by p to1uo1su1iomcchloride n ed so that they yield the desilfed color in each subsequentreduction. Still higher-developers of layer or kind of grain with theSame dissolved this kind can beprepared even from p-nitraniline develfmnand its higher substituted analogues, from ni- It ISunnecessarycomphcation to add trated naphthylamines and anthramines,with tures of 1nsoluble components and insoluble the aid of diandtrisulfonic chlorides mentioned Velopers to each emulsion and it harmsthe in the synthetic part of this description under transparency of thelayers, because a large 40 IV B. These polyvalent sulfonic chloridespermit cess of component must be present in order to also linking ofseveral molecules of w W m color e T is of Value 01?]?phenyl-h'ydroxylamine with ester formation and 1f 1t 15 e to ebtemdlfierent Wlth' subsequent conversion to the substituted p aminoh Samemsoluble compenent' as for exemPler phenol derivative. If nitrobenzolsulfonic chlohlgher Fnelecular, Insoluble afnephthol denve" ride is usedfor esterification and is reduced after e Wlth e and and linkedconversion, a further linking may be obtained by amino groups in thesecond nucleus, with the the polyvalent carboxylic acid chlorides or aidof two difierent developers: 'naphthol Ylelds nuric chlorides mentioned,because the external blue With l -amino-dime y red with D-. amino groupreacts more easily than that in the aminophenol(lthydroxynaphthoquinone-fi-hynucleus.

dr yanil). The water-soluble pm p n l i Higher derivatives ofp-amino-dimethylaniline of course, not added but may be used in the formare obtained in a similar manner, because the of its insoluble saltswith phosphotungstic acid, simpler substitution products are notsumciently etc., its 3-aminopheny1 derivative (developer Diinsoluble orstable, as for example, 2-anilino-, phenal?) or rather, and in around-about way, 5-3 3-dimethylaminoderivative, also the piperidinederivative, prepared with dibrompentane. It is diamine and analogues arealso suited for this,

if one amino group is dialkylated in the manner just mentioned, directlybysimpler or higher molecular residues or through hydroxalkyl ether. Itis finally nitrosated or coupled with a diazo compound, and the linked,highly-substituted pamino-dialkylaniline obtained by reduction. Thecorresponding derivatives of m-amino'phenol can also be used forchaining, and often the p-nitroor -nitroso compounds, so that thesubsequent azo-coupling can be dispensed with. Bis-derivatives are alsoobtained from the corresponding oo-diaminoor oo--dinitro-compounds ofdiphenyl, diphenyl-amine, diphenylene oxide, etc. by dialkylation in themannerdescribed and by introduction of a -amino group.. Both p-situatedamino groups in the oo'-dimethyl-amino-benzidine could be removed bydiazotization. then nitrosated to the dimethylamino groups in thepexample, fi-hydroxy-3-nitro-benzylchloride, arecombined withhigh-polymers cited underV at the end of the description.

It is better to add simple developing leucocompounds of dyes to theemulsions, preferably those which possess approximately the samedeveloping power. They must develop the exposed silver halide in sodiumcarbonate solution or weaker aikalies, and they must be insoluble in itor, in special cases, in alkali. It is, as a rule, advisable to conductthe development without oxygen, and in the same manner the followingwashing out of the unused leuco-form with alkali, or in those withsulfonic or carboxylic acid groups, with sodium carbonate, because alsothese insoluble or at least not diffusing and negligibly waterandsoda-soluble leuco-bodies are easily oxidized. Rather simply constructedleuco-developers should be combined with the emulsions so that they maybe easily washed out by sodium carbonate or alkali and yet yieldcompletely insoluble dyes. If the leuco-compounds are notentirely'insoluble in water, they can be precipitated within theemulsions as insoluble salts by phosphotungstate and similarinorganiccomplex compounds in a gelatine solution. In this absolutelyinsoluble state, they have no harmful effect on the silver halide,particularly if reduced inorganic complex compounds are used asprecipitants. Leuco-developers of acid character are precipitated byinorganic bases or higher molecular organic bases, as benzidine,naphthialso easily washed out basic dyes: auramine,

acridine yellow, thioflavine T etc.; or by poly-' ethylene polyamineslinked by cyanuric chloride and their quaternary ammonia compounds.Stabilizing -compounds may also be added to the emulsions, not onlythose mentioned in my patent application S. N. 139,759, now U. S. PatentNo. 2,226,639, but also sodium sulfite, salts of benzolsulflnic acid,also the sulfonic acids of triphenylmethane dyes or their bi-sulfiteaddition products. Salts or also alcohol may be added to the solution ofsodium carbonate or they can be more concentrated in order to preventdiffusion as much as possible in the event of decomposition of theinsoluble salts.

Suitable leuco-developers are principally the more stableleuco-compounds of my patent application S. N. 139,759, now U. S. PatentNo. 2,226,639 of December 31, 1940, as substituted hydroquinones,reduced lignone dyes and higher molecular generators of the same, asalso some vat dyes or stable leuco-forms of the latter and theircarbomethoxyand benzylcarbonic acid ester easily decomposed by sodiumcarbonate, ammonia or fixed alkali, or triphenylmethyl ester which canbe split more easily with acid, as well as other easily decomposed acylderivatives of the leucobodies.

Leuco-forms of indophenols, indamines and azo-methines where the dyesthemselves are not entirely insoluble in water, such as thymol blue orthe azomethine of aceto-acetic ester and N0- dimethylaniline, are notsuitable. Also the simpler leuco-bodies can probably be used only inform of insoluble salts, but rather the arylated leuco bodies or thoseof carbazol indophenols or halogenated leuco-bodies. Of specialinsolubility are the bis-compounds and still higher molecularleuco-bodies as they can be prepared with the following higher or linkedcomponents and the previous polyvalent developers by oxidation andreduction, which also holds true for the azomethines and the azomethidesinsensitive to acids, similarly to the carbazol indophenols.

B. Revmzsar. DnvELorMEN'r WITH INSOLUBLE CoLoa DEVELOPERS Complementarycolor negatives are obtained by the preceding method, and these resultin correctly colored positives by printing under the same conditions.There are two ways to obtain these directly:

(1) The latent images are first developed with a neutral non-couplingdeveloper, such as fer-. 'rous oxalate, as in the three-color reversaldedevelopment in sodium carbonate solution.

This has the advantage that insoluble color developers of differentrapidity can be used, because the primary development which determinesthe character of the part images was carried out in layers with the samedeveloper. It is unnecessary to counteract fog formation by largeamounts of potassium bromide or several percent of potassium iodide, aslong as absolute exclusion of oxygen is guaranteed. If insoluble saltsof high-molecular sulfonic or carboxylic acids of developers withquinine, etc., or phosphotungstate, etc. of basic developers are addedto the emulsions, it is of little importance. whether these salts aredecomposed by sodium carbonate or slight diffusion takes place, becauseprimary development and pre-treatment, together with several thoroughwashings have been survived by the color developers in the form of theirinsoluble salts. The unused-color substance is washed out by alkali,sodium carbonate or ammonia without oxygen. If the leuco-bodies arepresent in form of insoluble calcium-, barium-, magnesium salts,hydroquinone with acetone sulflte can also be used for primarydevelopment, and calciumor barium hydroxide for coupling.

Reduced azomethine from p-amino-dialkylaniline and palmityl aceticester, or better -anilide or diacylanilide serves for the yellow, thepyrazolone obtained from this ester and nitrophenylhydrazine, or betterthe. reduced lignone from two molecules of 2-phenyl-a-naphthol or thereduced hydroxynaphthoquinonimide from p-naphthoquinonef-sulfonic acidand p-aminophenol, aniline etc. for the red, and the leuco-indophenolfrom a-naphthol-2-carboxylic acid naphthalene etc, for blue-green.

It is less advisable to develop with sodium carbonate immediately afterexposure, and to destroy the primarily formed indophenol with acid, ifnecessary, in the presence of phosphotungstate or other precipitants, inorder to prevent solution of the unchanged leuco-body, and to make theresidual AgBr developable with thiourea etc., and then to develop thefinal image dye with sodium carbonate and to remove the silver. Theprimarily formed indophenol or indamine could also beconverted intoeasily washed out addition products by combining sulfite, bisulfite,thiosulfate, arylsulfinic acid with hydroxyor carboxylic groups, whichis particularly easy with the'carbazol indophenols, which are stable toacids and yield the most diverse colors. The residual AgBr is then madedevelopable and developed with sodium carbonate, the silver removed andthe addition products washed out with sodium carbonate or lye.

The middle emulsion can contain a leuco-derivative which is developedeven with very weak alkali, so that a possible diffusion does no harm,if sodium carbonate or lye are used for the two other leuco-bodies, orvice versa, the two easily developed leuco-derivatives can be in theupper and lower emulsions, provided they are not dissolved by weakalkali. The middle emulsion needs no developer at all and is developedafter completion of the two other images with a dissolved colordeveloper,

0. PRIMARY DEVELOPMENT WITH INSOLUBLE COMPO- NENTS Insoluble ornon-diffusing coupling components can also be added to the emulsion;these yield the corresponding colors with the same developer.

Fischer and Siegrist have tried this method of primary three-colorcoupling, but they failed in the application of this invention (Phot,Korr. 1914/18-22; 208-211) because technically it cannot be carried outin the form indicated by Fischer and Siegrist for the production ofcolor photographs with a triple layer or even a triple grain layer. Theinventors made the mistake of believing it necessary that the componentsmixed in the layers had to be dissolved first by the alkali of thedeveloping solution so that coupling could be accomplished (Ph. Korr.1914/22,

components from one layer to the other. even if gelatin layers areinterposed, so that only washed-out three-color images can be obtained.

The inventor claims it as his merit to have rec... ognized the fact thatcoupling is also possible in many cases with insoluble or nonor hardlydiffusing components, even in the presence of sodium carbonate or stillweaker alkalies. Most of the insoluble phenols, naphthols,arylsulfonylamines, etc., indicated later, are suitable, also in theform of insoluble lacquers, phenolates, complex salts, etc. Further,those sulfonic acids and carboxylic acids of these coupling componentswhich as alkali salts possess sufliclent amnity' to gelatine, so thatduring decomposition of completely insoluble salts and of those notharming the sensitivity which are added to the emulsions may be used,and no diffusion of any importance is to be feared by the alkalideveloper.

It was further recognized that. coupling with components havingproperties a mentioned be-' fore can also be brought about by the use ofundeveloped silver halide which was made developable by pre-treatmentwith proper substances, as 0.02% solutions of thiourea, thiosinamine andanalogous sulfur derivatives, or with a 0.001% solution of zinc chlorideby means of arsenite, hypophosphite, thallo salt, masking dyes or othersuitable agents which could be added to the developer; this is, however,not so favorable.

This primary three-color coupling can be used to advantage, if on oneside of a thin film, the red-sensitive silver bromide emulsion iscoated,

on the other side a yellow-green-sensitive silver bromide, and abovethis a highly sensitized silver chloride gelatine emulsion. The silverchlo ride emulsion can be developed first with a simple yellow developerunder conditions which do not affect the exposed silver bromide of thetwo other emulsions.

Primary three-color coupling can also be accomplished in such mannerthat the silver reduced by an ordinary non-coupling developer, as

' ferrous oxalate, is converted after fixing into silcomplementarynegatives were possible. which 211), which necessarily causes diffusionof the ver ferrocyanide, silver bromide, or better, into the morestrongly oxidizing silver chloride, by means of mercuric chloride.

D. REVERSAL DEVELOPMENT WITH INSOLUBLE 00M- I PONENTS The Fischerprocess had the great disadvantage, not counting all other defects, thatonly only by printing could be converted into the correctly-coloredpositive, A primary ordinary noncoupling development was not considered,because the components proposed in the patent, as aceto-acetic ester forthe yellow image, p-nitrobenzyl cyanide for the red, and a-naphthol forthe blue part image, are noticeably soluble in water, and therefore, donot survive, even without alkali, a general development with subsequentthorough washing, further removal or conversion of the reduced silverand repeated washing, without diffusing into the adjacent layers orgrains.

The residual silver bromide can be reduced after removal or conversionof the primarily separated metallic silver, with an ordinary developeror a reducing agent and can then be converted into silver chloride,because this acts much more vigorously as an oxidizing agent afterexposure or pre-treatment, or is more easily reduced, especially ifmercuric chloride is used for the conversion. Coupling is then alsosuccessful with slowly acting components. If salts decomposed by sodiumcarbonate are added to. the emulsions, ferrous oxalate, hydroquinonewith acetone sulflte or other neutral developers serve for reduction ofthe residual silver bromide.

The reduced, highly dispersed silver possesses a rather strongabsorption ability for dyes, and naturally, also the indophenols,indamines, azomethines, etc., which are combined, so-to-speak, in statunascendi. If the dyes or their sulfonic or carboxylic acids are notentirely water-proof, it is sometimes advisable to convert them intoinsoluble salts even before removal of the silver previously reduced.This-is especially true for indamines which are more strongly basic thanindophenols, especially if a color developer with several dimethylaminogroups or other basic residues is used, which results in especiallyinsoluble phosphotungstates, etc. 4

The pre-treatment of the residual silver bromide with thiourea andsimilar agents mentioned on the preceding page for coupling withpamino-dialkylanilines, p-amino-phenols,1,2-dihydroxynaphthalene-4-sulfonic acid, -carboxylic acid,-thiosulfonic acid, etc., represents essential progress in comparisonwith the exposure method because this presupposes removal of theprimarily reduced silver.

If the three latent images are first registered then the residual silverbromide made developable by prolonged exposure to ultraviolet rays orX-rays through the reduced silver, or by pretreatment with thiourea,etc., or exposure to white light after removal, or conversion of themetallic silver, the following methods are open for immediate productionof correctly colored positives:

(1) Second development with an approximately 1% solution ofp-aminodimethylaniline or analogues in a solution which is as littlealkaline with sodium carbonate as p a then the silver is removed withhyposulfite and potassium ferricyanide and the components washed outwith ammonia, alkali or sodium carbonate.

(2) One could develop at once primarily with p-aminodimethylaniline or'any other coupling developer, perhaps also p-aminophenols ordichlor-p-aminophenol, to an insoluble indophenol or indamine anddestroy this, as under B2, by the action of acids, or convert it bymeans of sulfite etc. into addition products which are thoroughly washedout only later. Even if no splitting takes place, the acids are washedout with the same facility as in the basic dyes of the Uvachromy inthose cases where stronger basic indamines are formed by coupling withpaminodialkylanilines which are substituted by dimethylaminoguanido-,biguanido-, or also quaternary ammonia groups, The indophenol.which istemporarily formed could also be reduced by thiosulfate, bisulfite orhydrosulfite which are partially without effect on the residual silverbromide. The leuco-forms produced are soluble in alkali and can bewashed from the residual components after formation of the final imagedye; then the procedure is as follows:

(a) The residual component is condensed in each layer to thecorresponding image dye after exposure or pretreatment of the residualsilver halide with p-aminodimethylaniline or another suitable couplingdeveloper in the manner described at the beginning. The temporary dye orits split products are then thoroughly washed out with sodium carbonateor alkali in which the final indamine is insoluble. If this does notcouple with diazo bodies, but the reduced original indamine 0rindophenol couples on account of its free hydroxyl group, diazoniumcompounds with many hydroxyl groups, also with carboxylic or sulfonicacid groups could be allowed toreact on it in order to obtain bettersolubility insodium carbonate.

(b) Diazonium salts can be allowed to react on the residual component,taking care in the choice of the components that azo dyes are formedwhich are correctly complementary colored as required by the theory,lemon-yellow, purple and green-blue. Indophenols, indamines orazometh'ines forming during primary coupling may show entirely difierentcolors. Unfortunately, it is very diflicult to find three colorlesscomponents of this type which yield the required dye with the same azobody. Pyrazolones usually couple with p-nitraniline to yellow ando-naphthol derivatives to red dyes; similarly also a-naphthois with4-position occupied; but a blue azo dye can hardly be obtained with it.It is simpler with films coated on both sides, because one can allowanother diazo compound to react on one side. The emulsions can also becoated in reverse order, so that the red-sensitive layer is on top, andthe green-blue part image is produced in this layer by any surfaceprocess. Another method is available by adding a colored component toone or two emulsions, in the simplest case, azoor triphenylmethane-, oranthraquinones dyes themselves which are capable of further coupling onaccount of hydroxyl and amino groups present. A yellow component can beadded to the upper and also middle emulsion, a red component to thelower emulsion; the latter two should produce the final purple orgreen-blue image dye. In order to prevent coupling of the finallemon-yellow dye present in the upper emulsion, during the action of thediazonium solution, but allow coupling of the two other components, theoand p-positions to the hydroxyl groups of phenol or naphthol can besubstituted by halide or partially also by alkyls, so that only theformation of indophenol is possible with substitution of the halide, butnot cou-.

pling to the diazo dye. If the emulsions contain amino compounds, thesecan be converted into derivatives of p-hydroxy-naphthoquinoneimides ofmostly red to blue color by development with1,2-dihydroxynaphthalene-4-sulfonic acid, 4-carboxylic acid or4-thiosulfonic acid. The abovementioned derivatives can be washed out byalkali. The amino dye remaining at the places of the residual silverhalide can be diazotized and coupled after coupling the residual phenolor naphthol, present in one or both other layers, with p-nitraniline. Inaddition to the coupling components, one can add a stable and insolublediazo body to the layers, r also the insoluble salt of an antidiazotateor of a stable diazonium compound, or an anhydride or its sulfonic acid,or carboxylic acid in form of insoluble salts. The two latter, however,are stable only to very weak alkalies and this must be taken intoconsideration in indophenol coupling of the component. The use ofantidiazotates is safer, because they are entirely stable to alkali;they must be converted into the diazonium salt by acid before couplingof the residual component. The precautions indicated in my Patent No.2,226,639 must be observed, since without them only poorly defined andunsuitable pictures are obtained. Components and diazotizable aminesindicated in these patents can be used in the emulsion, as in theinvention, but so that one does not depend upon the substantivity of thecomponents and dyes towards the gelatine, but mixes them in form ofinsoluble salts which are'stable to the developer, with organic orinorganic bases. In films coated on both sides, it is suficient to mixthem with one emulsion, or in a normal triple layer with two emulsions,since after completion of the two first part images, the residualcomponent of the third emulsion can be directly coupled with a dissolveddia-zonium compound. Ortho-aminobenzol sulfanilide which is insoluble inwater, is also as stable as the antidiazotate. The former is split bydilute mineral acids and then couples to diazo dyes; with the aid of thearylsulfamino group it also couples with the developer to indophenols.Analogous in their behavior towards the primary developer are also thoseaminonaphthols and other phenols with one, also external, aminogroup inwhich intramolecular coupling to a diazo dye takes place afterdiazotization, to which also diazo oxides and their sulfonic acids arecapable on prolonged action of alkali. One could also allownitroso-dimethylaniline, nitrosophenols, etc., to act on the residualcomponent, but this is without special importance.

If the residual component represents the generator of a dye formed byoxidation, it is oxidized to the final image dye and this especiallyholds true for the preliminary forms of lignone dyes and indigo dyeswhich develop much slower than they couple in sodium carbonate solutionor with still weaker alkalies. The insoluble higher homologues ofthio-indoxyl are less suitable. With the exception of some more stable(thio-) indoxyls of the anthraquinone and benzanthrone series,sulfurlindoxyl and (thio-) pyrindoxyl are the principal generators oflignone dyes for this purpose, to which in certain respects belong alsothe arylmethyl-pyrazolones which change to pyrazolone blue duringoxidation. Compounds which can be added to the lower emulsions aretetramethoxy-phenyl-a-naphthol, insoluble in water, or a higherpyrazolone, as phenylpalmitylpyrazolone, or higher analogues of-methoxynaph'thol which are easily prepared, or also 4-ethoxy-a-anthrol,etc. Compounds added to the middle layer are 2-phenyl-a-naphthol, alsoinsoluble 2-methoxy-a-naphthol or a-anthrol which all yield, withp-aminodimethyl aniline, indophenol dyes that are washed out ordestroyed in the primary development at the places of the latent image.The residual component is oxidized to the lignone dye by iron chloride,bichromate, persulfate, etc., in acid solution. The formation of theupper yellow part image in this manner presents difficulties. Yellowdyes with coupling hydroxyl groups or coupling groups attached could beadded to the upper emulsion, as salicoyl-ain water, or higher analoguesof,

aminoanthraquinone, the salicoyl derivatives of yellow dyes, etc., asfar as they are stable to the oxidizing agents used. If the upperemulsion contains silver chloride, the residual silver chloride can beconverted to yellow mercaptide with thioanilide which acts only on thiscompound.

(3) For primary development of the latent image, a developer is usedwhich, on account of the hydroxyl-, carboxylic acidor sulfonic acidgroup contained in its molecule 'is able to convert the addedcomponents, also with p-aminoarylsulfonylamines, as for example,p-aminoresoroin, p-aminophenol, or p-amino salicylic acid by couplinginto indophenol or indamine dyes which are soluble in water or sodiumcarbonate, whereby the color of the products obtained is immaterial.These dyes are washed out of the residual component either directly orafter formation of the final image dye, by bicarbonate,

borax, sodium carbonate, ammonium carbonate,-

ammonia, alkali, etc. depending on the circumstances. This can beassisted by splitting of the indophenol by means of acid, or byformation of more easily soluble addition products, as described under(2). 1,2-d'ihydroxynaphthalene-4-sulfonic acid, -4-carbonic acid and-thiosulfonic acid deserve special mentioning, because they permitcoupling to a soluble compound of insoluble components with aminogroups, especially of amino dyes, by formation2-oxy-a-naphthoquinoneimldes soluble in alkali or sometimes even insodium carbonate, especially, if also the other nucleus is substituted.

(a) Before or after removal of these (hydroxy) -indophenols, theresidual components are converted, according to (2a), (b) and (c), intothe final image dyes by repeated development with p-aminoalkylaniline,etc., coupling with diazo bodies or by oxidation.

(b) One could, of course, also proceed reversely with formation ofcomplementary colored'negatives by developing first generally withferrous oxalate, etc., then coupling the components to soluble compoundsat the places of the residual silver bromide and converting its residue,as mentioned, into the final image dye.

E. Rnvaassr. DEVELOPMENT WITH CoUrLrNo (LEUCO-) DYES residue of the dyederivative is converted into the I final image dye by oxidation,reduction or hydrolysis, the coupling products or their parts are washedout then or earlier with sodium carbonate, lye, ammonia or weakeralkalies or also acids in the case of basic dyes, and the silver isfinally removed with Farmers solution.

Only in the upper layer is it possible to add the final coupling dye inthe amount required for the formation of saturated images. They can beadded to all three layers, onlyfor printing purposes, because here onelayer can be sensitized for infrared which easily penetrates the dyes ofthe other two layers. According to earlier statements of the applicantthe coloring can be kept so light that the originals obtained appearsuificiently rich on white paper background, even if too weak forprojection.

A great defect of Fischers primary three-color coupler method was thatthe components showed very different coupling speeds (Ph. Korr.1914/22), so that aceto-acetic ester, for example, yields very weakimages in solution containing sodium carbonate. Of course, the reversaldevelopment automatically takes care of equalization, since thedevelopment of the residual silver halide can be extended to any desiredlength, especially, if the residual silver bromide has been convertedinto highly dispersed silver chloride in the manner mentioned before.

In order to obtain equal coupling speed in all I not permitted.

three emulsions, it was desirable to combine the (leuco-) dyes with thesame coupling group. In view of the fact that simple acylatedaminoanthraquinones represent excellent dyes, coupling algol dyes werepreferred, since they are easily prepared. Instead of acylating withbenzoylchloride, salicylic chloride, m-hydroxybenzoyl chloride,a-naphthol-2-carboxylic acid chloride, etc., are taken in order toobtain all colors of the spectrum with very simple aminooramino-hydroxyanthraquinones. The salicoyl derivative ofl-aminoanthraquinone is greenish-yellow, its 4- methylaminoand 4-methoxyderivative are blue, its 5-methylaminoand 5-amino derivative purple orred; by condensation with 44'-dibromdiphenyl, one obtains green-blue toblue-green dyes. By linking of several molecules with the aid of acidchlorides mentioned later under IV 13 a still greater variety of colortones is possible; in cyanuric chloride the first two chlorine atoms canbe converted with aminoanthraquinone or its alkyl derivatives and othersubstitution products,

then the last chlorine atom with m-aminophenol.

or an amino-a-naphthol. The algols can be convertedinto the very stableanthrone form or its condensation product with formaldehyde, thesocalled methylene anthrone, by suitable reducing agents in the knownmanner. The dye is finally regenerated from them by hydrogen peroxidecontaining sodium carbonate, persulfate, potasslum ferricyanide,preferably, however, by acid oxidizing agents. 1

Generally colored substances, even if they cannot be used in textiledyeing, can be combined with coupling acid chlorides mentionedundersyntheses IV, A and- C and other coupling phenols, naphthols etc. withreacting halides, by means of their own aminoor hydroxy groups, forexample, (leuco-) amino-malachite-green with salicoyi chloride etc. Onthe other hand, also chlorides of the carboxylic or sulfonie acids ofthe different (leuco-) dyes, also those of the anthraquinone group, canbe combined with m-amino phenol, amino-a-naphthol etc.,-also dyes with achloracetyl group etc. In order to obtain coupling products, thesulfonic chlorides are simply combined with aniline or a-naphthylamine,0- or p-aminophenol. The indamine formed during development, easilydecomposes by hydrolysis in the presence of acids or alkalies to thesulfonic acid amide of the dye which is insoluble in water and acids,but mostly in sodium carbonate.

The final yellow image dye can be added to the upper layer, a yellow orcolorless leuco-derivative to the middle layer, and even a red reductionproduct to the lower layer, if it is red-sensitive. Leuco-bodies canalso be added to one or two layers, a reduced red azomethine to themiddle layer and a leuco-indamine to the lower layer which develop theresidual silver halide even on immersion into a solution of sodiumcarbonate and produce the dyes.

wThe dyes must not be too highly molecular,

since the indophenols formed during coupling to a soluble compound withamino-resorcin, amino-salicyclic acid etc. are too difilcult to dissolvein sodium carbonate, and strong alkali is These (1euco-) dye derivativescould also be coupled directly in the primary development withp-amino-dialkylaniline to insoluble indamine derivatives and theresidual components removed by alkali, as under C, but this cannot berecommended, because only complementary color negatives are possible. Itis still less advisable to reimage to the two other layers.

duce the indophenols and azomethines resulting from them and to add themto the layers, analogous to A and B. Generally speaking, only theworking methods mentioned under (D1) (2) and (3) are of practicalimportance, while those described under (2a), (b), (c) and (d) must bechanged accordingly in order to create the final complementary-coloredimage dyes in each layer.

Contrary to this is the method of "fixed coupling," analogous to theprocedure of (DI) The latent image is first developed with ferrousoxalate or another neutral developer in the usual manner, then theresidual silver bromide is reduced with a coupling developer. Theindamine formed at these places is insoluble in lye, so that the.(leuco-) dye derivative which is still unchanged can be easily washedfrom theother parts, whereafter the silver is removed with Farmer'ssolution.

If, in the two preceding cases, the (leuco-) dye-indophenol formed orits oxidation product shall not be left as such in the image, theindophenol group is split by acid, if necessary, in the presence ofphosphotungstate or other precipitants for the basic indamine. The finalimage dye appears then to be combined only with a quinone orhydroquinone group and the latter has practically no effect on thecolor, the former only moderately so. The quinone residue can also bereduced to the hydroquinoneor pyrocatechine group which are sufficientlystable, as can be seen from many natural dyes.

Coupling to a soluble compound could also serve for the purpose ofremoving the residue of the perhaps colored components after primarycoupling development.

F. COMBINATIONS on THE Paoceouaas A-E AMONG THEMSELVES AND wr'rnTHREE-COLOR DEVELOP- Mam Simple color developers can be used for one ortwo layers, that is, insoluble components are added to only two or onelayers. Many variations are possible by combination with the numerousmethods of execution described in my prior application, but only fewseem to be of any importance. It is not easy to produce a brilliantlemon-yellow part image in the upper layer with acetacetic derivatives,as is required by the theory of the three-color photography, since thesederivatives couple quickly enough only in the presence of large amountsof alkali, they must also be present in large excess in order to yieldpure pictures; it is, therefore, preferable to develop in a simpleyellow developer. One can add insoluble or non-diffusing leuco-forms ofyellow dyes to the upper layer, as they are formed from thehigh-molecular. acid methylene compounds and p-nitroso-dimethylanilineor pnaphthoquinone-4-sulfonic acid described later, azothines andazomethides, and add components insoluble in sodium carbonate orcoupling (leuco)-dyes for the purple and green-blue part After generaldevelopment with ferrous oxalate, etc. and perhaps repeated exposureafter removal or conversion of the primarily reduced silver, orpre-treatment of the residual silver bromide with thiourea, etc.,

' color development is effected in the upper layer alone by immersioninto a solution of sodium carbonate; then the components of the twoother layers are coupled to the corresponding final or temporary dyes atthe places of the residual silver bromide by development withp-aminodimethylaniline,.etc., and the final-image dye produced,

if necessary, with the quinoneor hydroquinone group attached. Theresidual silver halide of the upper layer can also be exposed alone,provided the yellow filter dye or yellow coloring of the upper layer isstill intact, and it is developed with a dissolved yellow developer, asthose given in the main patent, for example, o-amino-symmetricalm-xylenol. All previously reduced silver is then removed or convertedinto ferrocyanide and the residual silver bromide of the two otherlayers exposed or made directly developable with thiourea, and the partcolor images developed with a coupling developer, finally all metallicsilver removed at once with Farmers solution.

Coupling components can very easily be added to two emulsions,preferably to the upper and lower emulsions, which even in the presenceof borax or bicarbonate yield dyes with p-aminodimethylaniline, whilethe last color image is formed in the third silver bromide emulsion witha dissolved direct-developer. Such a component can be present only inone, for example, the middle layer which can consist of silver chloride.This is developed first, then the two others are developed with sodiumcarbonate by self-development. One of the layers is preferably on theother side of the film or consists of silver chloride in order to permitindividual development.

An insoluble a-naphthol derivative can be in the lower layer, and ayellow component which is not entirely Water-proof, in the upper layer,while the middle layer contains no component. After general ordinarydevelopment, the residual silver halide of the upper layer alone isdeveloped with p-aminodimethylaniline causing coupling to the yellowimage dye, then the green-blue part image formed in the lower layer andfinally the middle layer treated with a dissolved purple developer. Thesilver is then removed with thiosulfate and potassium ferricyanide.

If components are in the upper and lower layers only, but not in'themiddle layer, and this middle layer which can also consist of silverchloride, is developed directly after general development with a simpleself-developer, a slight diffusion of the not entirely water-proof orsodastable components is of little harm, since they are separated by themiddle layer, together with the adjacent intermediate layers. A compounddeveloper can also be used last, if the unused components are previouslythoroughly washed out.

It is important to omit exposure of the re-' sidual silver halide of themiddle layer, since this presupposes removal or conversion ofallpreviously-reduced silver, if the use of thiourea is not desirable. In atriple layer with a component only in the middle emulsion, this isattained very simply in reversal development by coupling to a solublecompound this perhaps yellow-colored middle component or a couplingpurple or greenblue (leuco-) dye during the first general development bymeans of amino-resorcin, amino-salicylic acid, etc. If insolubledeveloping leuco-compounds have been mixed to the two other layers, onecannot, usually, use sodium carbonate, but has to use weaker alkalies asbicarbonate, borax, disodium phosphate, etc., since otherwise primarycolor development takes place. This indophenol image could, of course,be destroyed by acid or converted in the manner described into washableaddition products. The formation of the final image dye in the upper andlower layer is done only at this stage by immersion in a solution ofsodium carbonate, followed by coupling of the residual component of themiddle layer to a red azo dye through the action of a diazonium saltsolution.

When using dissolved simple color developers for the upper and lowerlayers, the procedure is analogous. The middle component is coupled to asoluble compound in the first general development by amino-resorcin oramino salicylic acid, etc., or coupled with aminodimethylaniline and theindamine formed is destroyed by acid or converted into washable additionproducts. The upper and lower emulsionsare then exposed one after theother and developed to the corresponding part color image, best withsimple yellow and green-blue or purple developers. The residualcomponent of the middle layer is then converted into the final dye ofthe last part image by coupling with a diazonium compound, perhaps alsobefore the colored development of the two other layers. If-the middlelayer contains silver chloride, one could, after coupling to a solublecompound in first development, reduce the residual unexposed silverchloride alone by prolonged treatment with quinone sulfonic acid andsulfite, or with dilute hydroquinone or the developers in- I dicated inmy prior patent application. By this a black separating wall is formedin the middle layer, so that independent exposure of theupper and lowerlayers appears to be guaranteed, when the filter dyes have beendestroyed or discolored, and also the sensitizing power is lost. Thesame effect is possible, if an insoluble vigorous ordinary developer isincluded in the middle layer which is able to reduce the residual silverbromide of the middle layer also without exposure.

With reverse order of the layers, one can add an insoluble a-naphtholderivative to the middle red-sensitized layer, and after coupling to asoluble compound and general development and drying superficiallydevelop the residual silver bromide of the upper yellow-green-sensitivelayer with seleno-indoxyl, then convert the residual component of themiddle layer into the greenblue indophenol by means ofnitrosodimethylaniline, and finally, after exposure through the back toblue light which cannot penetrate the yellow filter between middle andblue-sensitive layer, the residual silver bromide of the lower layer isreduced by a simple yellow developer, the silver removed and washed out.

The formation of the middle part image by coupling to a soluble compoundis of importance in combination with the methods of controlled Ydiffusion, as the preceding example shows forming only the upper partimage through superficial diffusion, then directly or after removal ofall silver which has been previously reduced, the lower part image. Thetriple normal distance between the upper and lower emulsions can, so tospeak, be created, if the residual silver bromide of the middle layer isdeveloped with an included insoluble developer or an ordinary dissolveddeveloper, after or without exposure or pre-treatment of all threelayers. Thorough washing out of the two residual components is presumed.

An insoluble leuco-indophenol or -azomethine for the green-blue orpurple part image can be added to the middle layer. After generalneutral development, the upper layer alone is exposed to blue light anddeveloped with a yellow developer without sodium carbonate, which isespecially easily possible with residual silver chloride, then the twoother layers developed to the middle part image by sodium carbonatesolution after pretreatment with thiourea etc. or the lower layer isdeveloped with a simple or compound color developer containing sodiumcarbonate. The upper part image could be produced also by controlleddiifusion or in any other manner, before or after completion of theother images.-

The middle emulsion can containan insoluble color developer, the othertwo components. The middle image is first produced in the presence ofsodium carbonate, then a solution of p-aminodimethylaniline containingsodium carbonate is allowed to act on the two other layers, whereby alight difiusion of the components which perhaps are liberated only atthis stage from their insoluble salts, is insignificant. n the otherhand, an insoluble component can be contained in the middle layer andthe two other layers contain insoluble color developers which develop onaddition of sodium carbonate, after which p-aminodimethylaniline isallowed to react on the middle layer. The middle layer may also containno additions at all and, at the end, is developed in color with a simpleor compound direct color developer. All this is principally intended forthe reversal process, less ;for primary coupling. Coupling dyederivatives described under E of the easily prepared leuco-indophenolsand leuco-azomethines could, of course, also be used as added insolublecolor developers.

The final (leuco) dyes capable of coupling can be added to the middleand upper layer, and the residual silver bromide only of the lower layerreduced to blue-green or purple with a simple color developer, eitherafter exposure through the back to red light, if it is stillsufliciently sensitive for this, or to blue light, if red or yellowfilters are between this and the middle layer.

In re-development, the middle layer can contain an insoluble a-naphtholderivative or other phenol which produces an insoluble green-blue imageeven in the first development with pamino-dimethylaniline, etc. This isthen fixed and rehalogenated and the two other layers developed in colorand finally the silver removed and washed out. One can also develop inthe usual manner and convert the primarily reduced silver into silverferrocyanide, then expose the residual silver halide and develop withp-aminodimethylaniline, whereby an indamine is formed only in the middlelayer which is destroyed by acid. One can also develop withamino-resorcin, p-amino-phenol or p-aminosalicylic acid and wash theindophenol out at the proper time. The silver ferrocyanide is thenconverted into silver chloride, the upper and lower layers exposed insuccession and developed individually in color, preferably with simplecolor developers. The residual a-naphthol derivative of the middle layeris coupled before or after this to the corresponding dye with adiazonium compound and the silver removed. The same procedure is used incontrolled diffusion. The regenerated AgCl or AgBr is made developableby exposure or pre-treatment with thiourea, etc., and the upper layerfirst developed by superficial action of a preferably simple yellowerdeveloper, then the lower'layer, and finally, the residual a-naphtholderivative of the middle layer converted into the purple azo dye. Thesilver ferrocyanide itself could also be developed in color.

In primary development with insoluble leucodevelopers in the middle-o!lower layer, an upper AgCl layer is first developed with a simple colordeveloper alone, then the layer containing the leuco-developer isdeveloped with sodium carbonate solution, and finally, the latent imageof the last layer with an ordinary color developer,

If the upper or middle layer or kind of grain consists of silverchloride without coupling component, an individual color development cantake place. The development of the yellow image can be accomplished witho-amino-symmetrical-mxylenol and borax, or about 0.1% sodium carbonatefor a long time; then followscolor coupling of the components containedin the two other layers with a solution of. p-aminodimethylanilinecontaining sodium carbonate, by primary, reversal or redevelopment,perhaps after preliminary conversion of the residual silver chlorideinto silver bromide or silver ferrocyanide, or KBr or potassiumferrocyanide is added to the new developer. If the upper AgCl layercontains a .coupling yellow dye, the residual silver chloride can beconverted. into silver ferrocyanide after coupling the yellow dye to asoluble compound in the first development. All silver and silverchloride can also be simultaneously converted by a mixture of potassiumferriand ferro-cyanide, after which the components in the two otherlayers are coupled to the corresponding image dyes by development withp-aminodimethylaniline in a weak solution of sodium carbonate. If theupper silver chloride layer contains the leucoform of a yellowazomethine, etc., the yellow positive image is produced after firstdevelopment with ferrous oxalate by bathing in the solution of an alkaliwhich is preferably weaker than sodium carbonate, then the residualsilver bromide of the two other layers is developed in color with directcolor. developers or by coupling with components added to these twolayers.

Silver chloride in the middle layer with nitrophenylmethylpyrazoloneadded is developed to the red part image with p-aminodimethylanilineeven in the presence of bicarbonate; with phenyl- J-acid and a smallamount of sodium carbonate the blue-green part image is formed. Theseweak alkalies are also suflicient for the formation of red to bluehydroxynaphthoquinoneimides when using1,2-dihydroxynaphthalene-4-sulfonic acid.

A blue-sensitive AgCl layer can be situated at the bottom, above it agreen-sensitive AgBr layer with an insoluble a-naphthol derivative whichis superficially sensitized also for red by pinacyanol. After generaldevelopment the AgCl alone is first developed in color, then bysuperficial diffusion of indoxyl, the AgBr.

G. COMBINATIONS wrrn CONVERSION-, MoapAN-rmo- AND Suamoa Paocassas Theoriginal silver chloride of the upper or also middle layer produced fromindividually reduced silver perhaps with lead ferrocyanide, can beconverted into colored ferrocyanides, complex compounds, mercaptides,mordanting bodies, precipitants oxidizing agents and tanning substances,etc., and the corresponding part color image be developed in the mannerdescribed there. Some of these processes are useful also for a triplelayer or a two-zone or two-grain double-layer, if they are changedaccordingly. If the upper part image is to be produce by pinatype,reverse order of the. layers is advised, the blue-sensitive emulsion atthe bottom. To a certain extent highly dispersed AgBr like silverchloride can be converted with thiophenols and anti diazotates can beused for the upper layer after ultraor high sensitization by suitabledyes, if very high aperture lenses are available. In this case it isbest to allow the converting solution to penetrate only superficially,so that the coarser grained AgBr oi the middle layer is not alsoaflected. Similarly, the highly dispersed metallic silver the upperlayer can be converted individually into AgBr or .AgCl by short timesuperficial penetra tion of a solution or potassium ferricyanide and KBror NaCl. This can then be developed in color or the silver chloride orterrocyanide be converted as just mentioned into the yellow upper image.Y

If the silver chloride or ferrocyanide is converted with antidiazotates,the solution of a component can be used for azo coupling, or it is inthe emulsion in an insoluble state. Since sulfonic acids and carboxylicacids do not attach themselves so firmly to gelatine, their insolublesalts with organic or inorganic bases, as cinchonine, diphenyl-,'andtriphenylguanidine, etc., are added to the emulsion. The silverantidiazotate is then converted into the diazonium salt by acid,observing precautions in order to prevent difiusion of the diazoniumsalt. The coupling is then dissolved out by sodium corbonate, perhapswith decomposition of the insoluble salt of the component sulfonic acid.The silver chloride or silver ierrocyanide could, of course, beconverted into mordanting substances for diazonium salts and thisallowed to react with the added component observing the sameprecautions. Be it observed that obviously according to the invention,isomerization to the diazonium compound and coupling to the azo dye canbe carried out in all three layers, in order to obtain sharp images.According to the invention, also insoluble, nonsulfonated phenols andnaphthols, amines and acid methylene compounds, especially, highermolecular ones are suitable.

Reduced silver or silver ferrocyanide containing AgCl which is presentat the image, yields colored ferrocyanides by the action of HCl withinsoluble carbonates, phosphates, etc., of certain metals contained inthe layers. Since vanadyland uranyl-ferrocyanide are unsuited on accountof their strong tanning action, titanium ferrocyanide is used, accordingto the invention, for yellow or also leadand zinc yellow obtained withchrome yellow from leadand ferrocyanide, nickel-dimethylglyoxime formedfrom nickel ferrocyanide is used for red. The residuel silver chlorideof the upper layer can be converted to the yellow mercaptide withthionalide. The middle layer can contain a coupling component forbluegreen, the lower layer an insoluble nickel salt, the upper layertitanium carbonate or vanadyl phosphate, which yield the correspondingdyes in the manner described, while blue-green results withp-aminodimethylaniline.

All the processes described here, serve, according to the invention,primarily for the production of reversal images of the residual silverbromide.

INSOLUBLE Am) NoN-Drrrusmo COUPLING Compo- NENTS methine dye formedbleeds even in several hours immersion in water on account of its smallmolecule. More suitable are esters with higher aliphatic alcohols orphenols, as well as the acetoacetic anilide and especially its higherarylides, also heterocyclic ones with dihydrothiotoluidine, or arylideswith one hydroxy1- or amino group which can be alkylated with cerylbromide or esterified with cerotinic acid chloride; also monoacetic acidbenzidide. Especially considered are also the higher aliphatichomologues, as undecyland palmityl acetic ester and their arylides. Therepeated introduction of the coupling function also yields betterresults, as is proven by the diaceto-acetic anilide andterephthaloyldiacetic acid anilide, even if the color obtained with thelatter is unsuitable.

The blue image expected from phenol and pamino-dimethylaniline does notappear,-because the dye is too soluble, and also the thymolblue iswashed out of the layer overnight by pure water. Ortho-hydroxydiphenylis better, and 1:5-dihydroxynaphthaline which yields on development withp-amino-dimethylaniline blue or dark-blue bis-indamines which are.almost entirely insoluble in water. The same holds true forpalmityl-phenyl-pyrazolone.

It is seen from these examples that by enlarging of the molecule of thecomponent or repeated introduction of the coupling group theinsolubility of the dye resulting from coupling is considerablyincreased. One is not dependent on double or triple combinations of thesame kind, but can also have entirely heterogeneous functions in themolecule: the a-naphthol or phenol group yielding blue indamines, thepyrazolone group yielding red azomethines, or the 1:3-ketonic acid groupand the 1:3-diketones shifting towards yellow. A mere enlarging of themolecule with indifierent residues decreases the yield of the dye. It istherefore more advisable in the synthesis to use more than one of thesame or different coupling groups several times in the new molecule.

A further requirement is that no diffusion of the components take place,either during superimposed coating of the three emulsions, or throughaction of the coupling developer. The most favored three componentsproposed in the patents mentioned: a-naphthol for the blueimage,aceto-acetic ester for the yellow image and p-nitrobenzyloylanide forthe red image, can in no respect be considered as insoluble in water.The latter, as well as most acid methylene compounds and the dibrom ortrichlor-a-naphthol often mentioned are soluble even in sodium carbonateand. still weaker alkalies. Since no coupling takes place at all in thedeveloper without alkaline reacting substances, or only very slowly, theinventors of those patents could not attain their goal.

These inconveniences are especially disturbing in reversal developmentwhich forms the most important part of the invention, because it allowsthe making directly of correctly-colored positives. Even if the slowerworking ferrous oxalate, hydroquinone-acetone sulfite or any otherneutral developer can be used for the first development of the latentimage, and the residual silver halide be made developable withthiosimanine, etc., without preliminary removal of the reduced silver,and neither repeated thorough washing nor the use of alkaline reactingsubstances in the coupling developer can be omitted.

There'was even the generalopinion until now entirely,

undoubtedly can be seen from the funda' ental work of Fischer andSiegrist (Ph.

Korr. 914/22, 211). I have now found that coupling also takes place withcomponents which are or at least practically, so insoluble in water thatthey do not difiuse into the adjacent layers to any appreciable extent(for example; tri-a-naphthol-triazine, a-naphthol-2-carboxylicacid-naphthalide, a-naphthol-4-benzoyl ketone, or its hydrazinecompound, but especially the high-molecular coupling components or theirinsoluble salts which are easily obtained by linking methods which willbe discussed in detail later), even if the developer is prepared withsodium carbonate or still weaker alkalies (borax, bicarbonate, ammoniumcarbonate, sodium glycocoll, etc.), also with fixed alkalies, if thecoupling component is insoluble in it, as the socalled cryptophenols.

Some of the azo-components in the insoluble state, are able to coupleunder vigorous conditions to azo dyes, yet this was uncertain in regardto the formation of indamines or ammethine dyes, and exposed silverbromide or that made developable by thiourea, etc., w' uld be able toperform such condensations by oxidation.

A certain improvement in the methods of coupling development is attainedeven if a practically insoluble component is introduced into the middlelayer, while the two other layers contain diflicultly diffusingcomponents. During the development, the unused yellow component willdiffuse, while the lower component only begins to diffuse, while theupper and middle image is developed for the greatest part. Difiusion canbe made very slow, if salts (sodium chloride, sodium sulfate, sodiumcarbonate, etc.) are added to the developer or the triple layer ispreviously allowed to absorb those salts, less practical with purewater, and only then immersed into the alkali-free developing solution.This salting out is generally applicable and 01! special importance inthe reversal of this invention, where these salts can also be added tothe solutions serving for the removal or conversion of the silver andfor pre-treatment of the residual silver bromide, if lower molecularcomponents are not even less certain, whether the coupling in'the senseentirely waterand sodaemulsion a possible substantivity of the componentto the emulsifying agent is of little importance and is rather to'beconsidered as a disadvantage on account of the difliculty of washing thesame.

Components containing a carboxylic acid group (1:5-dihydroxynaphthalene-dicarboxylic acid) or sulfonic acid group, havean individual position, since especially the latter often causes arather strong substantivity to gelatine which was recognized, when theless suitable "naphtholinsoluble or form inslouble salts with it whichare very diflicultly soluble, but not entirely insoluble, as forexample, aceto-acetic acid-diphenylamide, diphenyl-pyrazolone, etc.

In especially high-molecular coupling components or those which arecombined with colloids, the developer can also be prepared with ammonia,aliphatic amines and diamines, polyethyl enepolyamines or theirquaternary ammonia compounds, guanidine or fixed alkali, because thesalts formed by it show usually also high-colloidal character, andpossess no special tendency to diffuse, especially, if salts are addedto the developer.

To the insoluble, e. g. onor only difllcultly diffusing components, areto be compared their similarly obtained salts, themselves easily or nottoo easily soluble, e. g. diffusing components. Until now it was unknownthat these salts are able to couple with p-aminodimethylaniline duringdevelopment. The salt does not have to be absolutely insoluble, it issufllcient that it does not diffuse too much. This is determined notonly by the molecular structure of the component, but also of theprecipitant, because also sulfonic acid was suggested for this purpose.Although the finished dye is held more tenaciouslyby gelatine than theunused component, it is very diflicult to wash the latter outcompletely; it it is stable enough to light, it may be left in theimage, at least in motion picture films. Nevertheless, according to thepresent invention, high-molecular sulfonicand carboxylic acids ofcomponents as completely or approximately insoluble or non-diffusingsalts is recommended. Carbonyl-J-acid and p-amino-benzoyl-J-acid, forexample, as a-naphthol sulfonic acids, yield dark-green images indevelopment with p-aminodimethylaniline (the latter, however, not veryeasily), which are somewhat, but not completely stable to washing anddilute solution of sodium carbonate.

Aromatic hydroxyls and the acid methylene group do not cause asuflicient amnity to gelatine on account of their extremely weak acidcharacter, as can be seen from the relatively easily washed rosolic aciddyes, as well as from the non-sultonated phenoland a-naphthol azo dyes,although the latter are derived from one-sided diazotized benzidine or4-hydroxy-4'-aminodiphenyl or analogous substitution products ofdiarylureas, diphenyleneoxide, diphenylether, diphenylmethane, stilbene,diphenylamine, carbazol, etc. Dihalogenation in the oo'- or oppositionincreases the acid character, nevertheless, erythrosine and cosine, aswell as the still higher molecular brominated naphthofluoresceine andresorcln-anthraquinone belong to the easily washed out dyes.Halogenation brings about a certain afllnity to gelatine only in veryhigh-molecular coupling components. It is true for the acid methylenegroup in aliphatic, isocyclic and heterocyclic systems, whose aflinityto gelatine is increased by introduction of bromine into the methylenegroup, or also of nitro-groups into the nucleus.

The determining influence of the sulfonic acid group for the afllnity isvery well demonstrated by thiazol bases, where basic thioflavinc T isvery easily washed from gelatine, its sulfonic acid however, istenaciously held by it. Affinity to gelatine is present even when thesulfonic acid group is in the side-chain. Ethylene oxide can be allowedto act on the aminoor hydroxyl group and this esterified withchlorsulfonic acid.

substantivity is, however, a very extensible.

concept, because eventhe typically highly-colloidal azo dyes difiuse inspite of their sulfonic acid groups and this disadvantage is sodisturbing that measures must be taken to counteract it. It is nowonder, therefore, that the sulfonic acids of high-molecular azocomponents are by no means stable to the developers containing sodiumcarbonate; many of them can, however,

be added to the emulsions in form of their intically sufiicientsubstantivity for gelatine, but

the difiusion ability is determined simply by the.

enlargement of the molecule and the highly-colloidal character obtainedby it, and this spacefilling within the pores of the gelatine is much-more pronounced in the salts with higher-molecular bases.

It was found that in the a-naphthol and its 2- and 3-substitutionproducts, also in ketones, a halide-, sulfonic acidor carboxylic acidgroup in the 4-position is replaced, so that comolete v insolubleindophenols and indamines result. If the 4-positlon of the a-naphthol orthe p-pos 'tion of phenol is occupied by non-splitting residues, asalkyl, aryl, acoyl, carboxylic acid arylide, acylamine, etc., couplingtakes placein the 2-position, whereby a 2-halide-, sulfonic acid orcarboxylic acid group in, that place is also split oil The 4-derivativesof a-naphthol mentioned, also the tri- -naphthol-triazine, couple withp-aminodimethylaniline during development of the lai ftent image and inthe presence of sodium carbonate to blue-green indamines, 'while eugenoland di-isoeugenol yield black o-indamines with it. The ortho-couplingleads exactly as in the azo-p'ure coupling to more insoluble dyes.

In rarer cases, o-coupling takes place also in the development witho-aminodialkvlan lines.

By splitting of acid radicals in,the 4-position it is 'possible toobtain completely insoluble indophenols from coupling components whichcolor the gelatine substantively. These indophenols do not bleed, if theresidual components are removed as much as possible by vigorous washingwith solutions containing sodium carbonate or alkali. The affinity togelatine cou d be entirely removed by NO phenol or NO-resorcin withsplitting of the sulfonic acid group making the residual component moreeasily washed out.-

Since sulfonic acids are often of greater stability than naphthols, theycan. under certain circumstances, be left in theimage. Also halogenatedphenols are more stable to oxidizing agents, so that it is advisable toadd them to the layers as coupling components, if necessary. in form ofinsoluble phenolates. The same holds true, if the carboxylic acids, orsulfonic chloride of a phenol is combined with, (leuco) -dyes in orderto make them coupling.

Similar to the phenols or rather theirdihalide derivatives soluble insodium carbonate and to acid methylene compounds are thearyl-sulfonylarylamines which are formed just as easy as phee One must,however, take care that the 0- or p-positions are still available bybeing free or containing splitting 'halide-, sulfonic acid or carboxylicacid groups. Byapplying the methods given in the synthetic part of thisdescription,

under IV and V high-molecular products canbe obtained, that the sodiumcarbonate-solubility present in the lower homologues is lost, or thatthey are not even soluble in lye and in this respect approach thecryptophenols" as the still relatively simply constructeddodecamethylenediamine show. Ca, Ba, Mg, Pb and Zn salts are ofteninsoluble in water. In order to avoid split ting of these salts by thedeveloper, quicklime or caustic baryta is added to the developer insteadof sodiumcarbonate or lye. Insoluble salts are also obtained with highermoleculararomatic and heterocyclic bases, alkaloids, guanidines, dyesand other. precipitants, as is common with aromatic sulfonic acids. Mostof them are stable to a developer containing sodium carbonate, butcoupling takes place just the same. The solubility in alkalies can beremoved by alkylation.

- The aromatic amines couple much more dimculty in developmentawithp-aminodimethylaniline than phenols and naphthols, more, easily coupledare the. polyvalent amines, a m-toluylenediamine which'yields a blue,but not waterinsoluble image, the higher molecular amines, astetraminodiphenyloctane, or oo-tetramethyldiamino-benzidine, dithio mtoluylenediamine. The components can be added ,tothe emulsions asinsoluble phosphotungstates which are decomposed by a developercontaining sodium carbon-i ate; ,in the presence of salts, "however, nogreat tendency for diffusion ispresent. The aromatic and heterocyligamines, also (leuco-) dyes with a free amino group couple duringdevelopment with 1 :Z-dihydrQxymaphthaIene-4-sulfonic acid,-4-carboxylic acid, -4-thiosulfonic'aci'd, also with 3-chlor-derivativesin v eryaweak alkalin solution, into from red'to bluehydroxynaphthoquinoneimides.

In order to protect the sensitivity of the emulsion, it is usually notsuficient to add diffi'cultlyor non-diffusing components, but they mustbe added in form of(eompletely insoluble salts which can withstand thepreparatory operations of the reversal development; In the subsequentdevelopment of the residual silver halide, splitting of the salt by thesodium carbonate or other alkali in the developer can take place tofacilitate coupling, without fearing appreciable difiusion into theadjacent layers with high-molecular components, especially in thepresence of salts, as which are also considered alcohol, acetone, etc.,which,

If 4-sulfonic chloride of a-naph-- V ence of lacqueror complex-forminggroups, they are converted into insoluble lacquers or complex salts; apossible color change must be avoided by the proper choice of thecomponents or metal salts. The formation of internal insoluble salts Yis desirable, and instead OPp-amin -dimethyI- aniline,'it'is better touse its'dimethylamino derivative as developerior, this-purpose. It is,of

course, still more advantageous. to choose substantive components withsplitting sulfonicor carboxylic acid g'roupsi'n the manner describedbefore. v

Among the phenols or naphthols such highmolecular or substitutedorlinked representatives must be chosen which yield inthe perhapsnecessary alkaline development similar to cryptophenols, salts which donot or only'very diflicultly dissolve or: diffuse. Or-their insolublesalts are added to theemulsions with those organic or inorganicv baseswhich are decomposed only by the sodiuni carbonate of the couplingdeveloper, so that freephenolispresent only for a short time.

If insoluble Ca .or Ba-phenolates or naphtholates layer can be treatedindividually, especially, if developers of different developing speedsare used.

The insoluble components or their salts are added to the layers in aquanity of about 3 to grams per liter'of AgBr gelatine emulsion. Thedevelopers'are used in /3 to 2% solutions with about 5% sodium carbonateor the equivalent amount of weaker alkalies. The insoluble componentsare, if necessary, most finely dispersed in a 10% gelatine solution withthe aid of a colloid mill and this emulsion added to the silver halidecolloid emulsion. I

It is advisable to deposit the insoluble or nondiflusing components onthe silver bromide grain or to let them be absorbed. One should produceinsoluble naphtholates or insoluble salts of acid methylene compounds orsulfonic, or carboxylic are added to, the emulsions; their decomposition1 during coupling development is prevented by using calcium oxide orcaustic baryta instead of sodium carbonateand by conductingthe seconddevelopment without carbon dioxide and air.v It

is pointed out that naphthols yield insoluble phenolates not only withinorganic bases, but also with'organic, especially higher-molecularbases. Coupling components which are notentirely insoluble withcomplex-forming groups, as for example, o-hydroxy-acetophenone, theoximes of a-n'aphtholaldehyde, salicylicaldehyde, vanilline,o-hydroxy-acetophenone, 'o-hydrom-' quinoline, biguanido-a-naphthol,etc., can beadded to the layers in the form of their insolublecomplexsalts, which have been perhaps prepared from the finished dye.

Basic coupling components are added to the emulsions asphosphotungstates etc. or as insoluble salts with-higher-molecularorganic acids.

Before removal of the silver, the indamine dye which is often absorbedto it, can be made insoluble by these precipitants.

High-molecular coupling components, especially those which are combinedwith high polymers, (see-V) can often not be washed out, not even withdilute alcoholic lyes which are usually suflicient'for cryptophenols, sothat they'must be left in the image, unless they are unsuited on accountoi their color or instability in air. The removal of unused washablecomponents is best accomplished without air. Complete washing of thefirst developer is often unnecessary.

The triple layer with insoluble components can also serve for theprocedure of the main patent by developing each part image not withacolor developer, but with a coupling developer. In the choice of thecomponents, one should consider that subsequent corrections of theindividual part images are possible. One can add components of verydifferent coupling speed, even those which couple with borax, otherswhich couple only with sodium carbonate, so that each acids of thecomponents within the emulsion, preferably done after ripening, so thatno decomposition of the salts occurs, and because the absorption is ofspecial importance with fewer, dispersed silver halide. grains, onaccount of the larger inter spaces. Precipitation can be accomplished ingelatine-poor emulsions and the necessary' amount of gelatine added onlylater, or centrifu ed silver bromide or that which has been separatedfrom gelatine emulsion after dispersion in water, glycerine, etc., canbe used for this purpose; later, this can be finely divided in .gelatinesolution, washed out and replaced with the corresponding amount ofsensitizer. Completely insoluble higher-molecular phenols, naphthols,pyrazolones, etc. are dissolved in the necessary amount of alcoholiclye, this added to the silver halide gelatine emulsion of normal orconsiderably less than normal gelatine content and then precipitated bythe calculated amount of acid, brought to the correct gelatine content,

finely broken up and washed out.

The components do not absolutely have to be added to, the lightsensitiveemulsions, but may also be contained in a pure gelatine layer situatedabove or below the corresponding silver halide layer. The reversalprocess is best suited for this purpose, since the residual silverbromide is in direct contact with the gelatine layer containing thecorresponding coupling component which would be below in this case.Below the blue-sensitive layer, a layer with the yellow component isarranged, below the yellow-greensensitive emulsion, a gelatine layerwith the purple component, and below the red-sensitive emulsion, acolloid layer with the green-blue component. As indicated under 13, alsothe developing leuco-forms of the corresponding finished dyes could beadded instead of the components. One can add even the correct finaldyes, if they are combined, according to E, with a coupling Jfilters. 01course, only less sharp and weaker multiple color photographs of thecharacter of ozotypes are obtained.

As material for the execution of the present procedure, not only thetriple-layers, two-zone and two-grain double-layers of my priorapplication may be considered, but for printing also a three-grainlayer: one grain for green, another for orange and the last for infraredsensitivity or any other variations. Printing is done without bluelight, not only under black images, but also through multiple colorimages whose colors do not correspond entirely to those of nature, buthave been chosen with regard to the types of light necessary forprinting. In addition to the substances of my prior application used asfilter dyes for the triple layer, also the yellow dienol ofacetonedioxalic ester is considered, as red filter formacyls andhomophthalimide derivatives, which are all discolored at once by acid.and also the easily oxidized carmine red. The added sensltizers or thepart which is not absorbed by silver halide, are converted intoinsoluble or at least non-diffusing salts by acid or basic precipitants,as described in my prior application; excess precipitant may remain isthe layers. Properly chosen indifferent components or precipitants canalso serve at the same time as precipitants for the sensitizers. Thesame holds true also for the filter dyes.

All variants described before can also be used with one or two layers orkinds of grains. Especially numerous are the possiblities with filmscoated on both sides which can be so thin that during development apaper is used as support which is permeable to the developer. Alsoviscose film impregnated with highly-sensitized silverhalide can be usedcoated with silver halide gelatine or collodion emulsions and moderatelytanned on both sides.

The sound record can be arranged according to methods of my priorapplication, preferably in the layer nearest to the supoprt, in order toprotect it from damage. It is best to cover the border of the film atfirst, and before or after completion of the three-color image print thesound record on one, two or all three layers, also as primary orreversed silver image.

In the following, under I, II and III, the known or easily preparedmonovalentand polyvalent compounds which are more or less suitable forcoupling purposes, are given. Part IV is concerned with the syntheticpreparation of highmolecular components by linking of simpler ones,

Part V with the combination of simpler with high-polymer components.These syntheses are similar to those of the azo dye technique and areusually easily performed. They are involved almost exclusively with thereaction between acid chlorides and amines or phenols, alcohols, etc.,

which usually takes place easily in the presence of tertiary bases, suchas pyridine or diethylaniline. difiiculty. The preparation of thesensitive acid chlorides of phenols or amines which are often used, isbest accomplished by the excellent Ciba process (British Patent401,643). Until now, there was no special need for the formation ofhigh-colloidal components and dyes by the methods cited under V, becausethey have certain disadvantages in dyeing on account oftheir highmolecular structure, and the need arose only with the advent of colorphotography, so that only little data is available in the literature.

I. MONOVALENT PHENOLS I (a) Aromatic and heterocyclic phenolsAlpha-anthrol, also the hydrated form, o-- and m-hydroxydiphenyl,p-hydroxyand o-hydroxydibenzyl, o-hydroxy-stilbene, oandphydroxydiphenylpropane, oand p-hydroxy-diphenylethane and ethylene,o-benzylphenol, o-butylphenol, p-amylphenol, cyclohexylphenol, m-cresolwith one 4-heptyl, decyl, ceryl, groups, eugenol and The selection ofproper solvents is the only lsoeugenol, o-arylallyl phenols monoethersof higher pyrocetechines, benzyl-o-ethyl phenol, 2- hydroxy-l:3-diphenylbenzol, ene-diphenyl ether, hydroxy-diphenylene oxide, diandtri-isobutylene phenol, butyl-B-naphthol, 2- and 4-aryl-a-naphthcl, 4-and Z-aCyI-a DaDhthol, 3-aceto-e-naphthol and 2-aceto-a-naphthol,2phenyl-1:3-dihydroxy-naphthalene, 8-sulfamide-a-naphthol and its4-chlore-derivative, mnaphthol 3:6 disulfamide, 2'- anisa-l acetoanaphthol, hydrazides of o-ketophenols, 4-brom-pketophenols, chalcones,phenylhydrazines of salicylic aldehyde, of vanilline, etc., salicylicaldehyde compound of aminodiphenylamine and anils of otherphenolaldehydes, as well as their reduction products, especially thedifferent hydroxy-benzylnaphthylamines, salicylicaldehyde-semicarbazones, salicyiamine aldehyde, salicylic tetrazones,salicylal methylhexanone, salicylal acetophenone, etc., especially alsothe analogous compounds of a-naphtholaldehydes, as well as theirhydration products, e-triphenyl-p-(2-phenol-) ethane,hydroxy-triphenylmethane, 0- and phydroxy-triphenyl-carbinol andanalogous compounds, 2-hydroxy-hexamethoxy-triphenylmethane, hydroxyanddihydroxy-leuco-crystal-violet,

mand o-hydroxy-leuco-malachite green, 4-hydroxy-acenaphthene,hydroxyfluorene, hydroxychrysene, 3-hydroxy-benzofiuorenone,hydroxytetraphenyl-methane, cyanuric acid-dihydroxyphenyl ether, 1- and4-hydroxyxanthone and higher homologues, salicylal-hydrindone,tetrahydrolnaphthylphenol and similar products, as well as the hydratedamino-a-naphthols and their acyl derivatives, etc., dinaphthol-methane,oxidized '2:G-dihydroxy-naphthalene, as well as the formaline compoundof 2:7-dihydroxynaphthalene, 2-hydroxy-1 :8-phthaloyl-naphthalene,dihydroxy-phenyl-anthranol, hydroxylated mesophenylanthrones, tetraandocto-hydro-anthranol, hydroxylated flavones,benzolsulfone-mhydroxy-phenylmethane; o-hydroxy-phenyltolylsulfone,o-hydroxy-diphenylsulfide and other 0- hydroxy-sulfides and selenides,3-hydroxy-diphenylamine, .m-hydroxy-benzidine, a-naphtholpermimidine,hydroxy-phenyl-naphthindol, hydroxyphenyliminazol,hydroxyphenyl-aziminobenzolor -naphthalen, o-hydroxy-isoxazol,ohydroxy-guanazylbenzol, m-hydroxy-carbazol, 7-hydroxy-1z2-naphthocarbazol and analogues also tetra-hydrated.8-hydroxy-quinoline, p-hydroxy-naphtho-quinoline, reducedhydroxy-quinolines 2-phenol lepidine, 6-methoxy-m-hydroxy-Z-phenyI-quinoline and other phenyl-quinolines. D ehydrothiotoluidineand primuline base diazot1zed to phenol, 3-hydroxy-1:Z-naphthacridineand other hydroxy-naphthacridines, hydroxyflavinduline and itsdihydro-product as well as the compounds obtained through'addition ofmaminophenol or amino-a-naphthol, euxanthine and other xanthone dyes,sudan G, m-hydroxy- .azo-benzol, the products from salicylic aldehyde orvanilline with arylhydrazines, with anthraquinonylhydrazines, withazodye hydrazines, or with azo dyes themselves, as aniline, or withfuchsine and any other amino dye; further the reduction products ofthese dye anils, or stable coupling leuco-dyes themselves, among othersalso some N-acyl-hydroxy-hydrazo dyes, thianaphthenesulfone,homothioindoxyl, anthraquinonethioindoxyls, rhodamine and similar ringformations.

(b) Aroyl derivatives Most of the aromatic and heterocyclic-phenelso-hydroxy-propylof carbon tetrachloride, which substituted by mentionedbefore yield and p-carboxylic acids by the Kolbe salicylic acidsynthesis or by means through their chlorides or inthe presence of PC13easily form .the corresponding arylides with aniline, naphthylamines,anthramines, aminofluorene, dehydrothiotoluidine, primuline base,cholestylamine, cetylamine, cerylamine, myristicylamine and otheraliphatic and aromatic or .heterocyclic amines, especially also withthose amines which for further linking contain a nitro-group which is tobe reduced later, also one-sided with diamines or with benzoylhydrazine.

'These higher phenol-carboxylic acid chlorides yield esters constructedanalogous to salol and its known homologues and self-condensationproducts, for example, with 0-, pand m-hydroxydiphenyl, withhydroxyquinoline, quinine and cinchonine, with cholesterine,laurylalcohol, myricylalcohol, cerylalcohol, etc., also with ricinoleiccastor oil or its hydration product, as well as with other hydroxyandamino-compounds.

Instead of carboxylic acid chlorides, also sulionic chlorides, withnaphtholspreferably substituted in the second nucleus, can be used forenlarging of the molecule by the action on amines or phenols,aminonaphthols, etc., especially also the easily obtaineddisulfochlorides and disulionic fluorides of a-naphthol.

(0) Increase of the molecule by higher, in different radicals A veryextensive enlargement of the molecule is attained by esterification ofthe different anaphthol carboxylic acid chlorides and sulfonicchlorides, of the different o-hydroxy-quinolinecarboxylic acidchlorides, of salicylic acid chloride, of themethylphenylpyrazolone-carboxylic' acid chloride or sulfonic chloridewith amines or phenols, naphthols, anthrols which contain furtherhydroxyor amino group in the nucleus having been substituted in, themanner mentioned by high-molecular alkyls, aryls or acyls, in aminogroups also mixed, as ceryl-bromide, actadecyl bromide,laurylchloroacetate, also obtained from the mixture of higher alcoholsof natural waxes by saponification, or by reduction ofthe correspondingcarboxylic acids, cerotinic acid chloride or mixtures of higher fattyacid chlorides from natural waxes and fats, chlorcarbonic acid cetylicester, chlorides of sulfonic or carboxylic acids of anthracene,fluorene, etc. Excellently suited is also tri-anaphthol-triazine inwhich one or both residual hydroxyl groups are the radicals mentioned.Other esters concerned and containing a free hydroxyl group are those ofmannite, of the sugars or acetone sugar with palmityl chloride, oleicacid chloride further lecithine or diglycerides as car'- orap'-'distearine or the corresponding higher compounds with melissinicacid, erucic acid, etc.

The coupling acid chlorides mentioned at the beginning can be allowed toact further on: cholesterine-amine, cholestyl alcohol, cerylic alcohol,myricylic alcohol, dimyristicylic carbinol, p-hydroxyorp-amino-dibenzyland diphenyl propane as well as their reducednitrobenzoyl derivatives, diphenoxy-phenylanthranol and-diphenyl-anthranol, further on products which are obtained by allowingpor m-nitrobenzoyl chloride, after preliminary reduction to the aminogroup which is maintained as such, to react about four times on cetylorcerylamine, dehydrothiotoluidine and other aromatic or heterocyclicamines. In the same manner, one can easily as the amino group and thedanger exists that with more rigorous conditions the acid methylenegroup is also attacked. In the simplest case, one can allow thesecompounds to react, if necessary, in the presence of copper bronze,with: ceryl bromide, octadecyl bromide,

etc., laurylchloroacetate, m chloracetyl acenaphthene and -anthracene,further with the chlorides of the palmitinic acid, cerotinic acid,melissinic acid, oleic acid, erucic acid, also with ketostearinic acidchloride or ketoerucic acid.

chloride and prepare from these derivatives possibly thephenylhydrazones. Instead of using this acylating or alkylating agentdirectly, one can allow dinitrochlorobenzol, picrylic chloride,dinitrobenbylchloride, dinitrobenzoylchlorides, etc., to act before onthe aminoor hydroxy group of the component. One can also allownitrobenzoyl-chloride, anthranilic acid chloride, isatoic acidanhydride, etc., to act repeatedly on the original or newly introducedamino groups, as described in the preceding chapter.

Also the arylides of a-naphthol-2, -3-, and -4- carboxylic acid can besubjected to the reaction just described, if they possess a free ormonoalkylated amino group in the arylido residue.

In o-nitrophenol, etc., the hydroxyl-group can be alkoxylated byhexadecyl bromide, cerylor myricylic chloride, etc., after which,analogous to the Guajako synthesis, one reduces and converts bydiazotization into the high-molecular phenol.

The different dialkylamino-, phenylaminoand naphthylamino phenols and-naphthols, preferably substituted in the second nucleus, arepractically insoluble; also their N-acylation products, not only thoseof the m-series, but also those of the oand p-derivatives and a-naphtholwhich is perhaps also substituted by acylor carboxylic acid-arylidogroups in the 2- or 4-position, and this especially when using stearylor cerotyl chloride, etc. Also the NN'-diacetyl-disteryl derivatives ofthe 3:5 diarylamino phenols are suitable as components, and often showthe character of cryptophenols. Also very simply constructed components,as the ac.tetrahydroamino-naphthol, are excellent by their insolubilityin alkali, and, if necessary, they can be added in form of theirinsoluble phosphotungstates. On account of their strongly basiccharacter, they have a very favorable effect on the sensitivity.

Many of the phenols mentioned before yield useful 0- and p-ketones bycondensation with acids or their chlorides, similar to a-naphthol, whichare especially insoluble or colloidal when using higher fatty acids oraromatic acids, especially those which have unsaturated conjugateddouble bonds, as in Japan lacquer. The preparation of their completelyinsoluble phenylhydrazones is sometimes of advantage, While 4- ketonesof a-naphthol are very soluble in lye and sodium carbonate on account oftheir pronounced acid character, this is not the case with 2-ketones,its Z-benzoyl derivatives being not even soluble in N715 NaOH. Itmust,-therefore, be considered as practically insoluble and it is verysuitableas a coupling component, producing blue images on developmentwith p-amlno-dimethylaniline containing sodium carbonate. In addition tothe coupling components mentioned, the "cryptophenols" which werethoroughly studied by Auwers, are of significance on account of theirinsolubility in alkali or at least in sodium carbonate solution, ofwhich the oand p-hydroxytriphenylmethane should be especially mentioned.Similar to it is a modification of p-hydroxy-triphenylmethane carbinol,namely the easily obtained octo-hydro-anthranol and itsp-brom-derivative, the phenylimine of o-hydroxy-benzophenone,homothioindoxyl, benzanthrone-thioindoxyl, anthraquinone thioindoxyl.Also 1:3-diphhenyl-5-pyrazolone, very diflicultly soluble in water, ispractically insoluble in dilute alkalies, since its alkali saltsobtained with much caustic lye are dissociated by water, which isconnected with its very weak acid character. In the development with asolution .containing sodium carbonate violet-red images are producedwith p-amino-dimethylaniline. Its o-methoxy derivative hardly soluble inwater, is easily dissolved in alkalies.

Through the enlargement with high-molecular radicals, one can alsoobtain a high-colloidal, soapy character or complete insolubility 'ofmost salts of sulfonic acids of the components described herein, as isalready known of the reaction products from H-acid and stearylicchloride, etc.

II. POLYVALENT, NUcLEUs-CoNoENsEn COMPONENTS (a) PhenolsDihydroxynaphthalene, dihydroxyanthracene, mm'-and oo'-dihydroxydiphenyland their tetrabrom derivatives, o-bicresol, diisoeugenol, binaphthols,44'-dihydroxydinaphtyl-11' ketone; 22-dihydroxy 11' dinaphthyl-ar.octohydride, so-called diamino-oo'-dihydroxy stilbene or its NN-dicylderivatives, the difierent dihydroxystibenes as well as their halide andhalide-hydrogen-addition-products and their catalytically easilyobtained dihydroforms, dihydroxydiphenylquinone, naphtholfiuoresceine,di-(p-hydroxy-) phenyl-cyclohexanone, dihydroxytetraphenyl ethane,,methane, disalicylal-resorcin and -hydroquinone, disalicylal-acetoneand its hydration product diphenylene ketone-biphenol, 22 dihydroxy 11-dihydroxydiphenyl dibenzyltri-pyrazolones can be vdraznes, for example,those of benzidine, pp-

pared higher aliphatic homologues, acetone dicarboxylic acid. ester,acetone dioxalic acid ester (this can serve as yellow filter directly inits dienol form), terephthalolyl-, isophthaloyl-, naphthoyleneanddiphenyl -44'- dicarboxyl diacetic acid ester, as well as theirarylides, especially also with higher molecular aromatic amines. Alsoconsidered arethe' amino derivatives, sometimes easily split by acid;less valuable, however, are the thiourea and thiosemicarbazide additionproducts, but especially the monoand di-phenylhydrazones;' all thesealso one-sided in the acetoacetic acid-ester simply connected bydiamines and lfi-diketonesf on the other hand, this holds true also fordiacetoacetic anilide and its higher analogues. It is more diftlcult toprepare all these derivatives, if the acid methylene group ischlorinated or brominated which, however, presupposes diflicultsolubility.

Di-pyrazolones: They are easily prepared from the esters just mentioned,and also with he'terocyclic hydrazines as they may also be ob.- tainedby combination of aromatic amines with dehydrothiotoluidine or primulinebase by means of cyanuricchloride. On the other hand, diand producedalso from dihydiaminodiphenylmethane, oo'-diphenyldihydrazine, etc. Alsofrom diaminodiphenyl-hexane and -octane. Trihydrazines, as for examplefuchsine, or of its leuco-base, yield tri-pyrazolones, also thedifferent trihydrazines prepared with cyanuric chloride. Pyrazolonesbrominated in the methylene group often excel by complete insolubility.

(c) Metal-organic compounds The peculiar mercury compounds which areeasily obtained not only by combination of two molecules of phenol ornaphthol through Hg, but

. also by the entrance of one or two mercuric salt dianthralyl methanedihydrdxy diphenyl anthrone, bis-phenoland resorcin anthraquincne,addition pr'oducts of phenols with alizarine diquinone phenylimides ofdihydroxybenzophenones, mm dihydroxy diphenylamine, di

naphthol-66'-imine, 4 :S-dihydroxy-dibenzophenazine, dihydroxydinaphthazine. 2- 3'-hydroxynaphthoyl-2') 4 hydroxy 6:7benzo-pseudoazimino-benzol, p-hydroxyphenyl-6-hydroxy-quinoline, etc.,dihydroxy-diarylsulfones, phenol-o-disulfide, phenol p disulfide,dihydroxydiphenyldisulfide and -disulfone, cyclic duple-fi-xylylene-'mercaptol of m-hydroxybenzaldhyde and its tetrasulfone, condensationproducts of o-hydroxydiphenylacethydrazide with hydroxy aldehydes,cyanuric acid resorcin ether, diand tri-a-naphthol-triazine, alsocombined with other radicals.

(b) Acid methylene compounds Hydroxylacetic acid ester, succinyldiaceticacid ester, acetonylacetone-dioxalic acid ester, sebacyldiacetic acidester and the analogously preresidues into the molecule, are worthmentioning. They are precipitated by acids in completely insoluble formand can be added to the emulsions of silver bromide after thoroughwashing. If the mercury residue is in the p-position, it is replacedwith indophenol formation exactly as in diazo coupling.

It is of practical importance that also the acid methylene compoundsreact, and the washed acetateor chlor-Hg-compounds often couple withreplacement of the inorganic residue: Hg-ma- Ionic acid ester,Hg-aceto-acetic ester, Hg-acetoaceticanilide, Hg-Dyrazolones.

In certain respects, also the salts of the enol form of the acidmethylene compounds with other metals belong here, which are often verystable to developers containing sodium carbonate, ammonia, bicarbonate,etc., and can be added to the emulsions on account of their completeinsolubility in water, without reducing the coupling speed too much.Similar insoluble salts are also formed by the mono-brominated methylenegroup. The mostly yellow-green copper salts can easily be converted intothe blue basic salts. It is pointed out that the copper salts usuallyprecipitate in ammoniacal solution, the insoluble aluminum salts whichare stable to sodium car- 4 bonate and ammonia, are prepared even withand its higher homologues, as oxalyldiacetone,

benzoylacetone, dibenzoyiacetone, etc., a copper acetateis suilicient.

Also 0- and p-nitrobenzylcyanide yield insoluble copper salts; thep-derivative which is somewhat soluble in water yields also an insolublesilver salt.

Arylsulfonic acetic ester, -acetonitril, -nitromethane, etc., show asimilar behavior.

Pyrazolones which are usually very dim'cultly soluble after bromination'are practically insoluble, and often hardly soluble in sodium carbonate,can be precipitated as'a completely insoluble compound by copper-,aluminum-, zinc-, Caand other salts, also within the emulsion. Also thehigher-molecular organic bases often produce entirely insolubleprecipitates in the emulsion with coupling pyrazolones, naphthols andphenols.

lI'L POLYVALENT, DIRECTLY-LINKED Gourosanrs Coupling acid chlorides, assalicylic acid chloride, e-naphthol-2-, -3- or -4-carboxylic acidchloride, o-hydroxy-quinoline-l-carboxylic acid chloride,methyl-phenyl-pyrazolone-carboxylic acidor sulfonic chloride can also becombined with coupling a-naphthols, also the different aceto-aceticester-homologues, as for example, pahnityl acetic ester withamino-u-naphthol or with amino-arylides of the aceto-acetic ester itselfor with amino-pyrazolones.

eterogeneous bivalent coupling components are o-acetylacetone phenols,as z-acetyl-acetonep-methyi-phenol; 2-acetyl acetone 4 methylphenoi,Z-acetyl-acetone-m-naphthol. They can also be added to .the emulsionstheir insoluble copper-, aluminum-, zinc-, magnesium-, calciumetc. saltsor as ketonimines.

IV. POLYVALENT COMPONENTS LINKED BY INTERME- nIATE MEMBERS .4. Linkingof acid component by polyvalent bases (a) Linking of acid couplingderivatives by anilide formation:

It is assumed that one or two molecules react with primary amines, butthat of the latter, those of phenolcarboxylic acids are usually lessstable, more stable are diaceto-acetic anilide and its analogues.

Coupling derivatives are concerned:

(1) Acid chloride as: salicylic acid chloride, m-phenolsulfonicchloride, a-naphthol 2- or 3- or 4-carboxylic acid chloride or -sulfonicchloride, salicylic sulfonic chloride or oz-IlflDl'lthOl-Z- carboxylicacid-i-sulfonic chloride, naphthsultame -2- or 4-carboxy1ic acidand-sulfonic chloride, chlorides of the different o-hydroxyquinolinecarboxylic acids, chlorides of the products which are obtained by theaction of the acid chlorides mentioned on anthranilie acid,polyanthranilic acid or poly-pand m-aminobenzoic acid, chlorides of theaddition products of phenols and naphthols on unsaturated high-molecularfatty acids, chlorides of the reaction products ofa-IlflPhthOlSliHOIliO- or -carboxylic acid chloride on hydroxy-stearicacid, hydroxybehenic acid, ricinolic acid, etc., or on the hypochlorideaddition products of oleic acid, linolic acid, erucic' acid, ricinolicacid.

(2) Acid chlorides of pyrazolones, as sulfonic acid chloride andcarboxylic acid chloride of technical methylphenyl-pyrazolone.

(3) Aceto-acetic ester and especially its higher aliphatic, aromatic andheterocyclic homologues,

in the form of .dinaphthyls, diaminodianthranyl,

aswellas almitinicaclda'ceticesteraudtheum decylic acid acetic esteranalogously obtained.

Two molecules of these can be linked with formation of analogues ofdiaceto-acetic anilide by reaction with the same amino group ofsimpleramines or with diflerent amino groups with the use of diamines which,however, can also react one-sidedly.

Suitable polyvalent connecting members:

(1) Amines as for example: phenylenediamine, dlaminophthalene,diaminofluorene, benzidine, dianisidine, diaminobenzidine, and itssulfone, xylenylamine, diaminodixenylamine, tetraminodiphenylamine,tetraminodiphenyloctane, and its reduced tetra-nitrobenzoyl derivativediaminophenylenediimide and other diand tri-amines, as they are used inthe production of substantive azo dye acids, also heterocyclic onbonyl-bis-(p-aminobenzoyb) p-phenylene diamine or its disulfonic acid,diazo light yellow, etc., dinitrochlorobenzol, picrylic chloride,dinitrobenzoylic chloride, dinitrobenzoylic chloride can be allowed toreact on these substances or on simple aromatic and heterocyclic phenolsand amines and perhaps p-nitro-benzoylchloride on the reduction productin order to obtain highmolecular linking members after the reduction.

(2) Hydrazines are also considered as members as for example: hydrazine,iuchsinetrihydrazine, cyanuric trihydrazide, or its phenyl derivative.

(b) Linking of coupling acid derivatives by ester formation:

Derivatives mentioned under (a) can be allowed to react, in addition tothe coupling components mentioned before, with one or twohydroxylgroups, also with resorcin, diphenols, dihydroxynaphthalenes,hexaoxyterphenyl and other poly-hydroxylates, condensed hydroquinonesresorcyl-anthranol, dihydroxy-diphenylanthrone, further with glycol,glycerine, pentaerythrite, mannite, dipentaerythrite, saccharose,tetra-oxydecane, and with other natural or synthetic poly-alcohols, alsodiphenols with ketone groups or with the resins or Japan lacquerobtained from it, further with the hydroxyalkyh ethers easily obtainedfrom all these products by the action of ethylene oxide.

(c) Linking by (leuco) -dyes:

Connecting members are not only stable leucobases or leuco-cyanides oftriphenylmethane dyes, reduced gallo-cyanides orpolyhydroxy-anthraquinones, but also genuine dyes with aminoorhydroxylgroups, since in most of them the dye character is weakened orabsorption shifts towards yellow or orange occur by acylation. Fuchsineproduces a green dye with one molecule of salicylic acid chloride, alight yellow dye with three molecules. Triaminotriphenylmethane dyes orthe corresponding leuco-derivatives where only one amino group is in thep-position, are still better suited, or even those where this is not thecase, whereby the dye character is very much weakened or entirelydestroyed. Especially high-molecular derivatives are obtained with thbis-tetraminodemo-malachite green from tetramino-diphenyl-hexane or-octane, or its ieuco-cyanide or leuco-derivatives of analogous solubledyes.

Also most azo dyes are weakened or the color shifted towards yellow byacylation of their aminoor hydroxy-groups. Diphenyline ormm'-diamino-diphenyl can also be coupled after tetrazotization with twomolecules of u-naphthol and for example, car- All amino-c-naphthols,also with occupied 4-position and their 2- or 4-canboxylic acid aryl-"be esterified with the coupling acid chlorides, with possiblepreliminary or subsequent reduction to the hydrazo i'orm. Or the stablem-hydroxy-hydrazobenzol or the bis-derivative prepared analogously fromdianisidineis used directly. The stability of the hydrazo-forms can beincreased by the action of phosgene or acetaldehyde or potassium cyanideor potassium rhodanate on the azo body, or by esterification of bothnitrogen atoms of the hydrazo group with the coupling component.

(d) Linking by high-molecular intermediate members:

These are obtained by allowing salicylic acid chloride first to react,in a similar manner as for the formation of depsides, on the polyaminesmentioned under (a1) and (b) or polyhydroxyl compounds, leuco-fuchsine,trinaphthylguanidine, tetrahydroxydiphenylmethane, mannite,dipentaerythrite, rafilnose and other sugars, on pyrimidine sugar oranils of sugars, acetone sugar, etc., tri-a naphthol triazine, or oneallows 02- or fi-naphthol carboxylic acidor sulfonic chloride, isatoacidanhydride, or still better nitrobenzoyl chloride, nitrotoluol sulfonicchloride, nitrophenyl urea chloride, dinitrochloro-benzol, etc., toreact with them with subsequent reduction to amino roup. .Then, or afterseveral repetitions of the process, the coupling acid chlorides ornaphthols or pyrazolones are allowed to react. products obtained fromhexagalloyl-mannite, in similar manner, have an almost completelypolymeric character.

The

Three molecules of amino-naphthol, aminore- I sorcin, nitraniline,nitrophenol or nitronaphthol can be linked through cyanuric chloride ortriazine-tricarboxylic acid trichloride, and the former products thenreduced. The aminoor hydroxy-groups are possibly again acylated bynitrobenzoyl chloride or nitrotoluolsulfonic chloride and perhapsrepeatedly reduced. Only then they are esterified bya-naphtholcarboxylic acid chloride or the other coupling acid chloridesmentioned under (a) One chlorine atom of cyanuric chloride can also besubstituted by other residues, as ceryl amine, or by ammonia orm-aminophenol, after which one allows one Or two molecules of cerylbromide, cerotinic acid chloride to react. The same procedure can beused with the residual chlorine atom of di-a-naphthol-cyanuric chloridewhich can also be allowed to react with all simple and higher-molecularaminoand hydroxy compounds mentioned, especially also, it can bealkylated with higher aliphatic alcohols as cerylic alcohol, myricylicalcohol, etc.

High-molecular intermediate members are also obtained by the action ofchlorides of ketostearinic acid to be reduced later, hydroxystearinicacid, ricinolic acid, ricinolic ester acid, linolic acid, erucic acid,etc., on the aminoor hydroxy-,

compounds mentioned, followed by esterification with the coupling acidchlorides. Or, one proceeds in reverse order and allows salicylicchloride to react with hydroxystearinic acid, forming the chloride.

Both chlorine atoms of aa'-dlCh10Iydlil'le can be converted with thealkali salts of melissinic acid and the middle hydroxyl esterified bya-IlZDhthOlcarboxylic acid chloride or other coupling acid chlorides.

B. Linking of basic components by polyvalent acids Coupling derivativeswith amino-, hydroxyor sulfhydril-groups are for example:

ides, as '7-amino-a-naphthol-z-carboxylic acid naphthalide, as wellasthe one-sided products of hydrolysis, especially theacyclictetrahydro-lztiaminonaphthol further, omand p-phenylaminophenols,also the analogous derivatives 01 a-naphthol and a-anthrol as well astheir higher hcmologues (o-amino-toluolsulfonyl-) a-naphthylamine,aceto-acetic acid-hydroxyarylides, monoaceto-acetic acid benzidide,acetylo-acetatophenols and -naphthols, pyrazolones with free amino-,hydroxyor sulfydril groups, especially also the aminated acyclictetrahydronaphthylmethylpyrazolone from acyclic tetra-hydro-1:5-aminonaphthylhydrazine which is important on account of its stability.

An aminoor hydroxy group can be generally introduced into the arylidogroups of the coupling components mentioned under (a) for the purpose offurther linking, by allowing one molecule of salicylic acid chloride orpyrazolone carboxylic acid chloride to act on mor p-nitraniline, or twomolecules on nitrobenzidine, nitrodiphenyline or hydroxybenzidine andthen reducing the nitrogroup. Or 2- or 4-(m-bromacetyl) a-naphthol, alsom-chloracetamino-a-naphthol is allowed to act on nitraniline,nitrobenzidine, etc., and reduced. The nitro-group to be reduced canalso be in the aryl radical of a-naphthol-2- or i-ketones, which can beobtained with nitrobenzoylchloride, etc. Especially high-molecularproducts are obtained in this manner from diacetoaceticnitranilide, orby using 1:.5-dihydroXy-naphthalene dicarboxylic acid or of44'-dihydroxy-11'- dinaphthylketone-33-dicarboxylic acid. All thesenitro-derivatives yield dimer azoxyor azo-compounds of usually yellowcolor on reduction with glucose which also are suitable as components.

In all fundamental substances mentioned before, one could, of course,also allow por m-nitrobenzoyl chloride or p-nitrotoluolsulfonic chlorideto react with the free amino-', methylamino or hydroxyl group, reduce,and then only link, perhaps after trying to increase the side-chaincarrying the external amino group by repetition of the procedure. Inthis manner, for example, pamino-benzoyl-a-naphthol and its 3-sulfonicacid, as well as the analogous derivatives of a-naphthol with aminogroup in 2-, 3-, '7- or 8-position, can be obtained, perhaps with a4-sulfonic acid group, and also of the 4-amino-a-naphthol -2-sulfonicacid.

Also salicylic acid chloride can first be allowed to react with thesefundamental bodies, as well as m-or fl-naphthol-carboxylic acidchloride, and then only linked further.

Two molecules of these fundamental coupling substances can be allowed toreact with cyanuric chloride, and several molecules of the productobtained maybe converted with poly-aminoor poly-hydroxy compounds withexchange of the third chlorine atom.

Two or three molecules of a-naphthylamine or any other aromatic aminewith free por o-position can be linked by the diand tri-sulfonicchlorides to the phenol-like coupling arylsulfonyl compounds.

Connecting members are, for example: Phosgene, thiophosgene, carbondisulfide or ethyl oxalate, oxalylchloride, chlorides of adipinic acid,sebacinic acid, hexadecane-mm-dicarboxylic acid and still higheraliphatic di-acids easily accessible by electrosynthesis, iminodibutyric acid, benzoldicarboxylic acids, mand p-naphthalic acid, di-

benzyldicarboxylic acid, diphenyloctanedicarboxylic acid,benzophenonedicarboxylic acid, di-

phenyletherdicarboxylic acid, diphenylene-22'- oxide-44'-dicarboxylicacid, phenazonedicarboxylic acid, 'bisdiphenylene succinic acid,dithiotetrasulfonic chloride as well as its reduction product and theazo-body formed from it, also obtained from hydrazine and two moleculesof brom-metionic acid, as well as the chlorides from the analogouscondensation products with other aromatic or aliphatic di-'andpolyamines, chloracetylchloride, but especially cyanuric chloride andtrazine tricarboxylic acid trichloride. The simple or higer molecularpoly-aminoand hydroxy compounds or their hydroxyalkyl ethers withphosgene form polyvalent urea chlorides or isocyantas and chloracarbonicacid ester; by conversion with bromacetic acid and treatment withthionyl chloride, they form also polyvalent acid chlorides.

Several molecules oi polyanthronilic acid or analogues, or aliphaticmono-amino acids asthey are obtained by the reaction of the half acid ofsebacinic acid amide with hypobromite, are linked by phosgene or otherdiand tri-chlorides, the imino group is perhaps alkylated and thenconverted into the polyvalent acid chloride.

All acid chlorides mentioned before and also tetra nitrodichlorsulionecan first be esterifled with m-hydroxybenzoic acid or mor p-aminobenzoicacid and then the higher dichlorides produced with thionylchlorlde.

When using cyanuric chloride, two halides can be substituted by higheraliphatic or aromatic residues, for example, by two molecules of D-amino-stilbazol, and the residual chlorine is then directly brought intoreaction with amino-@- naphthol, or intermediate members are inserted.

Aliphatic polyacid chlorides must also be mentioned: several moleculesof ketostearinic acid can be linked by dior tri-hyd'razines (forexample, fuchsine, or its leuco-base or its leucocyanide); threemoleculesor ricinolic acid by cyanurlc chloride, etc., then treated withthionyl chloride or phosgene. Two molecules of a-naphtholcarboxylic acidchloride can be allowed to act on hydroxy-, dihydroxyordiamino-sebacinic acid, and the dichloride formed from it on twomolecules oi ricinolic acid or hydroxybehenic acid, as just explained.

If the polyvalent connecting member contains a hydroxylor reduced nitrogroup, further linkasoauo by the action oi phosgene on dyes with twoaminoor hydroxy groups.

C. Other linking methods (a) Linking by nitrogen-carbon combination withformation of:

Guanidines, especially diand trim-naphthaluuanidines.-One molecule ofthese compounds is allowed to act on thioureas from two molecules oi'amino-qgnaphthol in the'presence of lead oxide, or two" molecules oithis thiourea are linked in'the same manner by the action of analiphatic or aromatic diamine. This is also successiul with thioureafrom two molecules of aminostilbazol and amino-a-naphthol in the thirdposition.

Guanazill-- light-yellow insoluble o-hydroxy-guanazylbenzol issuitable,- the red p-monoxyiormazylbenzol' or the light yellowtetrazolium chloride are' less suitable, and the corresponding benzidinederivatives are somewhat better.

Hydrazides.'Formed from two molecules of a-naphthol carboxylic acid.

Hudrazones.--From salicylic aldehyde and semicarbazide, forming thesemicarbazone and azine, or also carbaminic acid hydrazone with aniline.Azine is also formed from two molecules of aceto-acetic ester, easilysplit by acids. It is important to note that not only a-naphthol-2- andi-aldehyde, but also 2.- and 4-ketones ot a-naphthol form azines orbis-arylhydrazones by linking oftwo molecules, similarly also the 4-sulionic acids and 4-brom-derivatives oi 2-arylketones. It is better touse higher-molecular aliphatic and aromatic dihydrazines, as under II,B, also diphenylmethane-dimethyl-dihydrazine.

com-

- ylenedibromide, etc., or better chlorinated petroleum is converted,ii! necessary, in the presence of native copper, with amino-a-naphthol,or analogously to ethyleneor trimethylene bromide with two molecules ofdihydroxybenzol, further pyrocatechinecarbonic acidhydrazide, using,however, bivalent intermediate members. Chloracetylchloride can beallowed to act on the before-mentioned amino compounds, for example, onleuco-c'yanide or leuco-base of bis-tetraminomalachite green and similarbistriphenyling through cyanuric chloride, trisulfonic chlo- Dyes canalso here serve as connecting memhere, for example prepared fromdiazotized,

fuchsine and three molecules of salicylic acid or phenol by the actionof chloracetic acid on the latter or other azo dyes with carboxylicacids containing 0H- or NH-groups, iuchsine, etc.,

methane dyes or basic dihydroxy dyes.

- (2) In the coupling body: Nitro-Br-a-naphthol is converted in thepresence of native copper with primuline base or its higher homologuesor derivatives with an external amino group, reduced and the aminefurther linked. Similarly used are m-chloracetyl-a-naphthol, 4- and2-mwhich are then converted into the chloride, or 75,

bromacetyl-a-naphthol, as well as m-chloracetamido- -naphthol.

; (b) Linking by nuclearcondensation:

Diketone formation, from higher dicarboxylic acids, as sebacinic acidand dihydroxybenzols.

Tri-a-naphthol-triazine, from 3 molecules of a-naphthol and cyanuricchloride, also with ogitidlrgezgyquinoline, a-anthrol and similar subandformazul compounds-The Pinacone formation, or benzoine condensation byreduction 01' -naphthol-4-ketones or 44-dihydroxy-dinaphthyl-1l'-ketone.

I Dianthrone formation, by reduction of coupling anthraquinonederivatives which are obtained from amino-anthraquinones and salicylicacid chloride, etc., or fromanthraquinone carboxylic acidor -sulfonicchlorides or -ureachlorides and -isocyanates with amino-a-naph-- thols.

V. Combination with high-polymers Suitable for reaction with theoriginal coupling bodies or those changed according to the inventionwith exchangeable halide, as mentioned in IV, A and IV, C, are: V

(a) Colloidal polyhydroxy compounds: I

(1) 0f the aliphatic series as: polyvinyl alcohol, polyalcohols obtainedby reduction from polymerized acrolein, etc., higher tertiary homologuesof polyvinyl alcohols obtained according to Grignard, polyacrylic acidesters, starch and polyamyloses, alkylcellulose or its water-solublepartial alkylether or that of polyvinylalcohol or acyl ester, also mixedwith methoxyland ethoxyl residues; further the hydroxylalklyethers ofall these compounds, as also of cotton,' fibroine, caseine, etc., which,in turn, can be partially alkylated or acylated.

(2) Of the aromatic series as: colloids obtained by polymerization ofphenols with unsaturated side-chains as vinyl phenols, vinyl-anaphthol,p-hydroxy-sty'rol, m-hydroxy-styrol, hydroxylated m-chlorandm-brom-styrols, poly-isoeugenol, vinylnaphtholcarboxylic acidesterhydroxyphenylbutadiene, hydroxycinnamic acidallyl ester,polymerized acrylic acid arylides of amino-' a-naphthols,benzal-o-hydroxy-acetophenone, the corresponding compounds with'a-tetralone and bis-derivatives, as disalicylalacetone, urushiol orJapan lacquer, phenolphthaleine; further condensation products fromphenol and colophonium, shellac or its easily re-agglutinateddisaggregates, tannin, maclurine, cafietannic acid, catechutannic acid,digallic acid, etc., depsideswhich can all be penta-acylated, productsfromv caoutchouc dibromide and phenol, phenol-formaldehyde resins ortheir intermediate forms, in as far as these synthetic or natural resinsand colloids are not in themselves suitable as coupling components.

(b) High-polymer amines:

These can be prepared in the simplest manner from the colloids mentionedabove by the action of nitrobenzoyl chloride or its oo'-dihalidesubstitution produce, nitroand dinitrobenzolsulfonic chloride,dinitrochlorobenzol, nitrophenylurea chloride, nitrobenzyl chloride withsubsequent reduction, or by means of isatoacid anhydride, anthranilacidchloride and other amino acid chlorides. Nitranilides can be preparedfrom polymerizing acids, as acrylic acid and cinnamic acid, and thesecan be polymerized and then reduced. Polyvinyl chloride and polyvinylbromide, polyvinyl-chloroacetate or analogous mixed polymerisates,halide-paraflines are converted with ammonia or amines, if necessary, inthe presence of copper bronze, to polyethylene-polyamines and otherpolyamines. When using .cyanuric chloride, one can also obtaincombinations with other aliphatic or aromatic amines. This is alsopossible with nitranilines which are reduced later, or

with nitroor aminotoluolsulfamide or hydrazide, here and in precedingcases. Polynitrostyrol,

polymerized nitrated cinnamicacid allyl ester, nitrated glyptalresina'nd other super-polymers formed from nitrophthalic acid andglycol, etc., are reduced to the amine. In cellulose one can, in somecases, effect an exchange of the acyl residues for ammonia or amines toamino cellulose and amino-thread,"amino-sugar andpolyethylenepolyamines. Aminofibroine is obtained byreduction of thecoupling products with diazo bodies of cotton, silk or albumen groundvery finely in the colloid mill; or diazotized silk or cotton isdirectly reduced, or they are coupled with aromatic amines to azo dyeswith several amino groups. One can allow nitroand dinitroarylsulfonicchloride or diazoxide-4-sulfonic chloride or 4'-carboxylic acid chlorideto act on peptone, fibroine, cotton, soap, etc., and then reduce. Alsothe polymerized reaction products of -1ormalin on aromatic amines areused, especially with p-naphthylamine.

Also here, one can introduce first indifferent intermediate members, asethylene oxide or salicylic acid chloride, anthranilic acid chloride,isatoacid anhydride, etc., into the polymers with hydroxylor aminogroups. Difierent coupling bodies can also be combined with the samehighpolymer linking member, or the hydroxylor amino groups which are notused by the same coupling body, are esterified with chlorsulfonic Inaddition to polyvinyl bromide, for the linking of the coupling aminoorhydroxy derivatives of phenols, naphthols, pyrazolones, aceto-acetichomologues and their carboxylic acids mentioned under I V, B, one canalso use polychloroprene, polyallyl chloride, polyvinylnaphthalenebrominated in the second nucleus chloro-caoutchouc and other halideaddition products of caoutchouc; further polyvinylchloroacetate,polyacrylic acid chloride, and the products obtained by means ofphosgene or chloroacetylchloride or chloracetic acid and thionylchloride from cellulose and other polyhydroxylor polyamino compounds,with reacting halide, also partially by means of cyanuric chloride.

The combination, according to A and B can also be accomplished beforepolymerization, by allowing linolic acid chloride to react withamino-a-naphthol, or -naphthol-carboxylic acid chloride withhydroxyl-styrol, salicylalacetophenone, urushiol etc., or with theesters of nitrobenzyl alcohol with cinnamic acid, acrylic acid, etc.,after preliminary reduction to the amino group.

2 molecules of (amino-)a-naphthol can be linked by cyanuric chloride,and this product be allowed to react with the poly-compounds of A, or,after exchange of the residual chlorine atom for the amino group, withthe intermediate members of B, or with'a coupling body with an externalamino group.

' What I claim is:

l. A process of multi-color photography which 7 layers developable,developing the film in a weak- 2. The process of claim 1, in which thedye corresponding to. the original dye compound is regenerated by theuse of hydrolysis.

3. The process of claim 1, in which the dye 5 corresponding to theoriginal dye compound is regenerated by the use of an oxidation step.

KARL SCHINZEL.

